Re:Let's honor James Doohan, aka "Scotty".
on
Win the X-Prize Cup
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· Score: 1
How many Gs do you think an antimatter drive would generate?
How many do you want? You can generate a huge amount of thrust using antimatter, but you don't have to. Starting thinking along the nano- and microgram scales and you'll get the picture.
Though this is pretty far into the future in any case. There's no way that antimatter production is in any way cost effective at this point. Sure it's a great way to get an exceedingly light fuel with a huge amount of potential power, but considering cost is one of the biggest issues, we aren't going to see it used for a long, long time.
My great great grandparents came to America with no solid job prospects.
That was an incredible achievement, but you must realize that they completely expected to be able to breathe and drink the water when they got to America. Oh, and they also were pretty sure that there would be enough atmospheric pressure to keep their eyes from bleeding.
It's one thing to step into the unknown when you know the unknown won't kill you. It's another when the most basic of necessities are completely gone.
This is a niche in a niche market. Yes, a relatively huge number of 64-bit capable chips are being sold by AMD currently, but they're at best only half of the recent chips sold, so overall still a very small portion of the market. And what number of those chips actually run a 64-bit OS? That's even small compared to the overall linux market, which is already pretty damn small.
I expect this will change very quickly once a 64-bit Windows OS actually goes final.
This is a bit short sighted. Not entirely, but somewhat. It's great that you're needed on site, as am I in my job, but what happens when "on site" is actually in India?
There will always be IT service jobs that require on site service (McDonald's needs to have IT support to sell burgers, hospitals need their systems maintained, etc.), but when we talk about product development, it can be done anywhere.
The IT industry will slowly become like the US auto industry. We don't actually make cars in the US anymore, we just assemble them, the majority of the parts are prefabricated and shipped in from cheaper manufacturers outside the US. Just like Honda and Toyota.
The software doesn't need to be written here or managed here. Right now we sell software written in English translated for other languages, it's no harder to do the oppposite.
The only software would be nearly have to be written locally would be for various US governments, especially those that require clearances unavailable to foreign workers.
3. The next year, when the contract expires, Walmart goes to A and says "This year your products will be sold for price (X - $1). If you can't give me that price, we're done doing business."
It's even worse than this. From Company A's perspective, Walmart doesn't have to ask for a lower price, they could just keep the price the same and inflation would cause the same problem.
The price reduction just makes this worse. And Walmart's "we lower prices regularly" policy makes this necessary from Walmart's perspective.
What really scares me about the article is when Walmart basically sends in consultants to "help" Company A reorganize to stay profitable. Suddenly, Walmart has a lot of say in how those companies are run. Walmart technically doesn't own these companies, but they practically do.
Though I don't have any actual information on the subject, my guess is that they make the metadata of secondary import. They write the file out and if that's successful they get the metadata for it, as translated through the file type plug in.
This way, things will only be out of sync when something fails after the file write. With periodic integrity checks (say, done through a journaling method) the synchronization can be fixed by querying the file (which was saved) during this check using the same method. Yes, searches would not work correctly for this file prior to the integrity check, but if the write to the metadata store has failed for some reason for this file, I'm guessing the user will have bigger problems searching in general, not only for this particular file.
I know in the past that Apple has done something similar, under OS 9 (possibly starting in OS 8). It would actually update the metadata store on a timed basis. Of course, this was more of a keyword index, but it was metadata nevertheless.
I really hate writing "me too" posts, but those last two sentences are spot on. Parents have to appreciate and encourage their childrens' education for their children to get one.
If the children don't care because their parents just see school as free day care, it won't matter how much money we throw at the schools or how lively and wonderful the teachers are. The kids won't learn if their parents don't care.
General "Buck" Turgidson : Doctor, you mentioned the ratio of ten women to each man. Now, wouldn't that necessitate the abandonment of the so-called monogamous sexual relationship, I mean, as far as men were concerned?
Dr. Strangelove : Regrettably, yes. But it is, you know, a sacrifice required for the future of the human race. I hasten to add that since each man will be required to do prodigious... service along these lines, the women will have to be selected for their sexual characteristics which will have to be of a highly stimulating nature.
Ambassador de Sadesky : I must confess, you have an astonishingly good idea there, Doctor.
Now I guess he might have made a mistake in his algorithm, but what if it turns out that it works most of the time, so you can solves 99% of the cases of a specific NP problem with a good heuristic that is in P ?
If it doesn't solve 100% of the problems, nope. Doesn't prove a thing about P's relation to NP. Assuming his algorithm is correct, it's just a clever algorithm.
Of course, it also might be the case that he just managed to prove that this problem was never really an NP to begin with, much less NP-complete. If it was only assumed NP and he managed to completely solve it (100% of the cases) in P time, then it has no effect on the group of NP-complete problems since you'd be unable use this MST-based solution for all NP-complete problems.
After all, for some travelling salesman problems, some parts of the solution are obvious.
Again, if parts are obvious, but the whole is not, this has no effect on the P/NP relationship. Heck, given a set of cities in a line, the TSP can be solved with a Nearest Neighbor solution (O(n^2)), perfectly, every time. Or even more silly, given only two cities, the solution is obvious. It's the general solution for all cases that's the big deal. If I remember right, to guarantee a perfect TSP solution, it's along the lines of O(n!) or possibly O(n^n) though I believe the first one is correct.
I agree that it should be a republic, but considering that a country as diverse as the US is represented by rich, white men, I'm starting to think that the definition of "represented" has been changed.
I think I make decent money; that and being single helps a lot...
Actually, being single isn't so good, being without kids definitely helps. Get yourself a spouse who works full time too. Two people basically live only slightly more expensively than one. If they both work, the total income doubles.
Television fakes 60 frames per second by switching out half the frame at a time (every other row). That's what the "i" vs. "p" means in the video formats that everyone's jabbering about. "i" is interlaced, "p" is progressive.
Motion picture projectors do something similar. They've by definition progressive, one whole frame at a time, but they have a lower frame rate than even TV; it's something like 27 f/s. They trick your eye by illuminating every frame twice.
It goes like this: first they show you a frame, then the slotted rotating disk (I can't remember the name for this) blacks it out by moving to a solid section, this it rotates to show the same frame again. In the next blackout, the next frame is moved into place and the cycle repeats.
Re:An additional word about 'blocky trans..'
on
Star Wars on DVD
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· Score: 1
Such a stupid, pointless change because apparently, Spielberg doesn't like gun violence now.
I'm not sure why Spielberg did this. You can't say that he doesn't use guns, since he did direct Saving Private Ryan, which definitely had plenty of guns. He also co-produced Band of Brothers, which had a pretty impressive array of violence.
I think it's more because it was a "kids' movie" in his view. Personally, I thought the guns were appropriate. If you've got a ton of government alien hunters running around in the woods, it seems logical that they'd have guns.
Not if they're losing money on each $.49 sale. If they sell a single song at.99 and make less than.50, then any number of sales at.49 are going to be at a loss.
For a more specific example, let's say they make 30 cents per 99 cent transaction with the 70 cents remaining going into care and feeding their servers, bandwidth costs, RIAA fees, etc. If they sell that same song for 49 cents, they're going to be in the hole 21 cents per transaction.
Bottom line: Twice as many songs at half the price would make them lose more money than the same number of songs at half the price.
I'd just like to point out that Puerto Rico is not alone in this distinction. There are a number of US territories throughout the world, among them American Samoa, Guam and the Northern Marianas Islands. The US doesn't really come close to the territories that the Brits still have lying around, but it takes a long time to deconstruct an empire upon which the sun never sets.
Also, I'd like to not that this isn't limited to offshore lands either. The District of Columbia (the DC in "Washington, DC" for those watching at home) is actually under approximately the same non-representational government. There is a single representative in Congress, who is not allowed to vote except on committee and more or less doesn't get much say. Heck, DC license plates actually say "Taxation without Representation" on them.
Actually, I bet it'll be more like several families will pull together the funds to buy a single computer to share. You also have to remember that this won't just be a computer as we think of them. This will be more like a dorm room machine that also is used as a TV, a DVD player and a phone, which they probably don't have currently either.
For a more 1st world example, think of all of the people who bought the PS2 when it first came out because they were basically getting a DVD player for "free".
Yes, the Olympics is political, but I think the politics are more positive than negative.
To counter your example, I'd like to point out that North Korea and South Korea are again competing together as "Korea." This may not be a big step, and I doubt that it will change the political situation in those countries in the near future, but I would bet that no matter where side of the Korea divide they're from, Koreans are cheering the unified team before other countries.
Think of it as a first step in a grass roots movement.
Why not make it a tablet? Let's talk about the specs for a portable display:
An LCD display. (Duh.)
WiFi to talk with the basestation (the CPU box in this case) or the Airport Express directly (where's the CPU in this case?)
A way to decode video. The better the video codec, the thinner the stream (which for wifi is necessary or you'll flood the network) and the faster the decoder necessary. So there's going to be a processor, either general purpose or single prupose (video decoder).
On board battery. It's a portable display. Portable. It needs a battery.
A touch screen. This is optional for a purely display function, but I can't see it as very useful without some kind of interaction available. So we've got some kind of input, which means we definitely have to be able to talk back out to the network instead of just blindly receive, which takes some more processing ability to set up the outgoing data and send it.
Okay, so let's review. We need a display, something to decode and encode data, take input and talk to a remote source all powered by a battery. Wow, it sounds pretty much like a laptop to me, except it has no keyboard or hard drive.
Basically, we've already got a battery powered bundle of processing power. It's already going to cost a fair amount to manufacture, why not go all the way and make this a tablet PC, so that you can save the cost of the basestation (traditional CPU). A tablet PC can be used as a portable display and can also be used to write a document. To set it up as a desktop, you can just set it on an easel and sit a bluetooth keyboard and mouse in front of it (Apple already makes them) or just include a USB port.
Ford never stated he invented the automobile. The patent that the grandparent was referring to was owned by George Selden for the "Road Engine". In retrospect, it was a patent that was broadly applied to all internal combustion automobiles. The patent was administered by an automobile company consortium called the Association of Licensed Automotive Manufacturers.
Ford refused to pay the royalties necessary and the patent was in court for years. In the end, Ford won because they limited the scope of the patent to a particular kind of engine that no manufacturers actually used at the time. From the reading I've done, it was more to allow Ford to keep manufacturing without all of his customers being sued than anything else.
If you've got a robotic exoskeleton and a wide area network, why not just pilot the soldier remotely?
Electro-magnetic emissions. A human soldier can turn off his WAN/LAN if he doesn't want to be detected. A remote controlled robot becomes about as useful as a boulder when this happens.
Unless you want to use trailing cables of course...
Look how well it worked out for the Autoworkers Unions from the 70's and 80's. They were a powerful group that got absolutely crushed because they thought fighting a free market economy was a good idea.
Actually, with US-based companies the various UAW-type unions are still incredibly powerful. So powerful that I believe they're hurting the industry. Such unions were very important when you were forced to work 7 days a week, 16 hours a day for barely a living wage, but in modern times (just this last decade) autoworkers' unions have demanded things like profit sharing. Profit sharing for an unskilled hourly employee who has a quota low enough that he can sit around part of every shift? In a job where they unions protect you from getting fired? I don't think so.
You can now purchase a computer and load it up with OpenSource software enough to make people highly productive for less then $300 a computer. Take a look 10 years ago. You couldn't hardly get a computer for under $1,000.
I disagree with this. Software was an incredibly small percentage of the cost 10 years ago. In fact, as you go back, the software was less and less expensive. It was the hardware that cost money. Yes, today software is a much larger percentage of the cost, but the cost has decreased mainly because of cheaper hardware, not hugely more expensive software.
We currently have about 135 years of paper archives dating back the the late 1800's.
Though it would be incredible to have all of this online (or the even greater archive available from NYT), what they are charging for are things that have been on the web since 1996. It's not like they have to send someone off into the stacks to find, scan/type and upload a 75 year old article, they just have to do a database lookup, just like they're doing with the current articles.
In other words, it's already electronic from end to end, but they're charging $3 an article.
What I don't understand is that using current ads, much of this older content can actually make money again, something that newspapers haven't really been able to do before. Currently, if someone wants to read an article from 5 years ago, they go down to their local library, find it on microfilm and read it. The original paper doesn't see any money at all. If they made these archives available online, they'd at least get new ad revenue.
Uh, Marathon was originally written to run on the 68000 line. In fact, I ran it on 68030s and 68040s for several years.
68000 line was a CISC line. A pretty darn good one at that.
Of course, when Apple switched over to the PPC line, Bungie switched with them. I don't really know if they ever ported the Marathon games over, but they ran well under Apple's 68k emulator. I do know that their line of Myth games ran both on the PPC and Wintel boxes. In fact, their most recent Myth release ran under OS X as well.
Heck, I'm just surprised that they released Halo for OS X after they were bought by MS.
Basically by going to fuel cells you are setting up all the required infrastructure (no small feat) for an easy transition.
I think that "no small feat" is a major understatement. Yes, as long as we can figure out a clean way to generate electricity (difficult, especially when you start narrowing the definition of "clean"), we can easily keep changing the original source energy of the hydrogen as better methods come along.
The problem is that the infrastructure problem is huge at just about every level. It's hard to store large quantities of hydrogen at fuel stations because hydrogen escapes easily. It's hard to transport hydrogen for the same reasons. It's hard to carry enough hydrogen in an individual vehicle because it has incredibly low energy density and must be kept under high pressure to make up for it. This is also a problem for the above fuel stations since some kind of apparatus will need to be maintained to keep it under pressure; fuels that are liquid at room temperature stay nicely in cheap tanks underground.
Then there's the more minor issues. To move gasoline/diesel around a local system, you need a fairly simple set of pumps. To move hydrogen, you need high pressure seals and safe ways to connect and disconnect them without increasing the cost drastically.
Hydrogen may burn cleanly (yes, fuel cells "burn" hydrogen), but the infrastructure change is tremendous.
Has anyone tried creating a hybrid biodiesel? The existing infrastructure could be used from a renewable fuel source. There should be very nice fuel efficiency numbers from that as well.
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How many do you want? You can generate a huge amount of thrust using antimatter, but you don't have to. Starting thinking along the nano- and microgram scales and you'll get the picture.
Though this is pretty far into the future in any case. There's no way that antimatter production is in any way cost effective at this point. Sure it's a great way to get an exceedingly light fuel with a huge amount of potential power, but considering cost is one of the biggest issues, we aren't going to see it used for a long, long time.
That was an incredible achievement, but you must realize that they completely expected to be able to breathe and drink the water when they got to America. Oh, and they also were pretty sure that there would be enough atmospheric pressure to keep their eyes from bleeding.
It's one thing to step into the unknown when you know the unknown won't kill you. It's another when the most basic of necessities are completely gone.
This is a niche in a niche market. Yes, a relatively huge number of 64-bit capable chips are being sold by AMD currently, but they're at best only half of the recent chips sold, so overall still a very small portion of the market. And what number of those chips actually run a 64-bit OS? That's even small compared to the overall linux market, which is already pretty damn small.
I expect this will change very quickly once a 64-bit Windows OS actually goes final.
There will always be IT service jobs that require on site service (McDonald's needs to have IT support to sell burgers, hospitals need their systems maintained, etc.), but when we talk about product development, it can be done anywhere.
The IT industry will slowly become like the US auto industry. We don't actually make cars in the US anymore, we just assemble them, the majority of the parts are prefabricated and shipped in from cheaper manufacturers outside the US. Just like Honda and Toyota.
The software doesn't need to be written here or managed here. Right now we sell software written in English translated for other languages, it's no harder to do the oppposite.
The only software would be nearly have to be written locally would be for various US governments, especially those that require clearances unavailable to foreign workers.
It's even worse than this. From Company A's perspective, Walmart doesn't have to ask for a lower price, they could just keep the price the same and inflation would cause the same problem.
The price reduction just makes this worse. And Walmart's "we lower prices regularly" policy makes this necessary from Walmart's perspective.
What really scares me about the article is when Walmart basically sends in consultants to "help" Company A reorganize to stay profitable. Suddenly, Walmart has a lot of say in how those companies are run. Walmart technically doesn't own these companies, but they practically do.
This way, things will only be out of sync when something fails after the file write. With periodic integrity checks (say, done through a journaling method) the synchronization can be fixed by querying the file (which was saved) during this check using the same method. Yes, searches would not work correctly for this file prior to the integrity check, but if the write to the metadata store has failed for some reason for this file, I'm guessing the user will have bigger problems searching in general, not only for this particular file.
I know in the past that Apple has done something similar, under OS 9 (possibly starting in OS 8). It would actually update the metadata store on a timed basis. Of course, this was more of a keyword index, but it was metadata nevertheless.
If the children don't care because their parents just see school as free day care, it won't matter how much money we throw at the schools or how lively and wonderful the teachers are. The kids won't learn if their parents don't care.
Dr. Strangelove : Regrettably, yes. But it is, you know, a sacrifice required for the future of the human race. I hasten to add that since each man will be required to do prodigious... service along these lines, the women will have to be selected for their sexual characteristics which will have to be of a highly stimulating nature.
Ambassador de Sadesky : I must confess, you have an astonishingly good idea there, Doctor.
If it doesn't solve 100% of the problems, nope. Doesn't prove a thing about P's relation to NP. Assuming his algorithm is correct, it's just a clever algorithm.
Of course, it also might be the case that he just managed to prove that this problem was never really an NP to begin with, much less NP-complete. If it was only assumed NP and he managed to completely solve it (100% of the cases) in P time, then it has no effect on the group of NP-complete problems since you'd be unable use this MST-based solution for all NP-complete problems.
After all, for some travelling salesman problems, some parts of the solution are obvious.
Again, if parts are obvious, but the whole is not, this has no effect on the P/NP relationship. Heck, given a set of cities in a line, the TSP can be solved with a Nearest Neighbor solution (O(n^2)), perfectly, every time. Or even more silly, given only two cities, the solution is obvious. It's the general solution for all cases that's the big deal. If I remember right, to guarantee a perfect TSP solution, it's along the lines of O(n!) or possibly O(n^n) though I believe the first one is correct.
Republics are supposed to represent the people.
Actually, being single isn't so good, being without kids definitely helps. Get yourself a spouse who works full time too. Two people basically live only slightly more expensively than one. If they both work, the total income doubles.
Motion picture projectors do something similar. They've by definition progressive, one whole frame at a time, but they have a lower frame rate than even TV; it's something like 27 f/s. They trick your eye by illuminating every frame twice.
It goes like this: first they show you a frame, then the slotted rotating disk (I can't remember the name for this) blacks it out by moving to a solid section, this it rotates to show the same frame again. In the next blackout, the next frame is moved into place and the cycle repeats.
I'm not sure why Spielberg did this. You can't say that he doesn't use guns, since he did direct Saving Private Ryan, which definitely had plenty of guns. He also co-produced Band of Brothers, which had a pretty impressive array of violence.
I think it's more because it was a "kids' movie" in his view. Personally, I thought the guns were appropriate. If you've got a ton of government alien hunters running around in the woods, it seems logical that they'd have guns.
For a more specific example, let's say they make 30 cents per 99 cent transaction with the 70 cents remaining going into care and feeding their servers, bandwidth costs, RIAA fees, etc. If they sell that same song for 49 cents, they're going to be in the hole 21 cents per transaction.
Bottom line: Twice as many songs at half the price would make them lose more money than the same number of songs at half the price.
Also, I'd like to not that this isn't limited to offshore lands either. The District of Columbia (the DC in "Washington, DC" for those watching at home) is actually under approximately the same non-representational government. There is a single representative in Congress, who is not allowed to vote except on committee and more or less doesn't get much say. Heck, DC license plates actually say "Taxation without Representation" on them.
For a more 1st world example, think of all of the people who bought the PS2 when it first came out because they were basically getting a DVD player for "free".
To counter your example, I'd like to point out that North Korea and South Korea are again competing together as "Korea." This may not be a big step, and I doubt that it will change the political situation in those countries in the near future, but I would bet that no matter where side of the Korea divide they're from, Koreans are cheering the unified team before other countries.
Think of it as a first step in a grass roots movement.
- An LCD display. (Duh.)
- WiFi to talk with the basestation (the CPU box in this case) or the Airport Express directly (where's the CPU in this case?)
- A way to decode video. The better the video codec, the thinner the stream (which for wifi is necessary or you'll flood the network) and the faster the decoder necessary. So there's going to be a processor, either general purpose or single prupose (video decoder).
- On board battery. It's a portable display. Portable. It needs a battery.
- A touch screen. This is optional for a purely display function, but I can't see it as very useful without some kind of interaction available. So we've got some kind of input, which means we definitely have to be able to talk back out to the network instead of just blindly receive, which takes some more processing ability to set up the outgoing data and send it.
Okay, so let's review. We need a display, something to decode and encode data, take input and talk to a remote source all powered by a battery. Wow, it sounds pretty much like a laptop to me, except it has no keyboard or hard drive.Basically, we've already got a battery powered bundle of processing power. It's already going to cost a fair amount to manufacture, why not go all the way and make this a tablet PC, so that you can save the cost of the basestation (traditional CPU). A tablet PC can be used as a portable display and can also be used to write a document. To set it up as a desktop, you can just set it on an easel and sit a bluetooth keyboard and mouse in front of it (Apple already makes them) or just include a USB port.
Ford never stated he invented the automobile. The patent that the grandparent was referring to was owned by George Selden for the "Road Engine". In retrospect, it was a patent that was broadly applied to all internal combustion automobiles. The patent was administered by an automobile company consortium called the Association of Licensed Automotive Manufacturers.
Ford refused to pay the royalties necessary and the patent was in court for years. In the end, Ford won because they limited the scope of the patent to a particular kind of engine that no manufacturers actually used at the time. From the reading I've done, it was more to allow Ford to keep manufacturing without all of his customers being sued than anything else.
There's more info Here
Electro-magnetic emissions. A human soldier can turn off his WAN/LAN if he doesn't want to be detected. A remote controlled robot becomes about as useful as a boulder when this happens.
Unless you want to use trailing cables of course...
Actually, with US-based companies the various UAW-type unions are still incredibly powerful. So powerful that I believe they're hurting the industry. Such unions were very important when you were forced to work 7 days a week, 16 hours a day for barely a living wage, but in modern times (just this last decade) autoworkers' unions have demanded things like profit sharing. Profit sharing for an unskilled hourly employee who has a quota low enough that he can sit around part of every shift? In a job where they unions protect you from getting fired? I don't think so.
You can now purchase a computer and load it up with OpenSource software enough to make people highly productive for less then $300 a computer. Take a look 10 years ago. You couldn't hardly get a computer for under $1,000.
I disagree with this. Software was an incredibly small percentage of the cost 10 years ago. In fact, as you go back, the software was less and less expensive. It was the hardware that cost money. Yes, today software is a much larger percentage of the cost, but the cost has decreased mainly because of cheaper hardware, not hugely more expensive software.
Though it would be incredible to have all of this online (or the even greater archive available from NYT), what they are charging for are things that have been on the web since 1996. It's not like they have to send someone off into the stacks to find, scan/type and upload a 75 year old article, they just have to do a database lookup, just like they're doing with the current articles.
In other words, it's already electronic from end to end, but they're charging $3 an article.
What I don't understand is that using current ads, much of this older content can actually make money again, something that newspapers haven't really been able to do before. Currently, if someone wants to read an article from 5 years ago, they go down to their local library, find it on microfilm and read it. The original paper doesn't see any money at all. If they made these archives available online, they'd at least get new ad revenue.
68000 line was a CISC line. A pretty darn good one at that.
Of course, when Apple switched over to the PPC line, Bungie switched with them. I don't really know if they ever ported the Marathon games over, but they ran well under Apple's 68k emulator. I do know that their line of Myth games ran both on the PPC and Wintel boxes. In fact, their most recent Myth release ran under OS X as well.
Heck, I'm just surprised that they released Halo for OS X after they were bought by MS.
China: 1,298,847,624 (July 2004 est.)
India: 1,065,070,607 (July 2004 est.)
Population growth:
China: 0.57% (2004 est.)
India: 1.44% (2004 est.)
These are all from the CIA World Fact Book (available online). Looks like China's still ahead, but India will be catching up pretty shortly.
I think that "no small feat" is a major understatement. Yes, as long as we can figure out a clean way to generate electricity (difficult, especially when you start narrowing the definition of "clean"), we can easily keep changing the original source energy of the hydrogen as better methods come along.
The problem is that the infrastructure problem is huge at just about every level. It's hard to store large quantities of hydrogen at fuel stations because hydrogen escapes easily. It's hard to transport hydrogen for the same reasons. It's hard to carry enough hydrogen in an individual vehicle because it has incredibly low energy density and must be kept under high pressure to make up for it. This is also a problem for the above fuel stations since some kind of apparatus will need to be maintained to keep it under pressure; fuels that are liquid at room temperature stay nicely in cheap tanks underground.
Then there's the more minor issues. To move gasoline/diesel around a local system, you need a fairly simple set of pumps. To move hydrogen, you need high pressure seals and safe ways to connect and disconnect them without increasing the cost drastically.
Hydrogen may burn cleanly (yes, fuel cells "burn" hydrogen), but the infrastructure change is tremendous.
Has anyone tried creating a hybrid biodiesel? The existing infrastructure could be used from a renewable fuel source. There should be very nice fuel efficiency numbers from that as well.