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Portable 8-iMac Linux Cluster Real World Debut
Snocone writes: "Here is the first real world application (researching drug effects on the brain, ironically enough) of Terra Soft's 8-way Black Lab Linux cluster.
Even if they didn't deserve mad props for standing up proudly against the Lintel hegemony, there's just something fundamentally hilarious about selling an $18K supercomputer made out of iMacs." So - eight Imacs. You could get the different colors, and call it a Lifesavers Candy Cluster?
I use PC's and can tell you that IRQ sharing, although it is possible, does not always work between certain devices. Especially old PCI cards that were built before IRQ sharing was implemented. If IRQ sharing worked 100% of the time maybe the Mac people wouldn't have so much to complain about. This will never happen though because companies can't be expected to make sure their card works with every other card out there. Only that it complies with the standard.
The Sound Blaster Live's SB16 emulation has been terrible on my system. I had to move my ethernet card to a different slot so Win98 would start. Otherwise it would lock before it even started the interface. Of course, that is probably a special case because the SB16 emulation requires it's own IRQ.
It would be much better if we as users didn't have to deal with IRQ's if we didn't have to. The fact of the mater is, even with IRQ sharing, we still have to deal with IRQ's on occasion so that things will work as they should.
Taddeusz
-- Ignorance is the pinnacle of religion - Me
I especially liked the 4 industrial strength, rubber-coated casters - being near the top of the list I'm guessing they're more important to the functioning of the cluster than the switch, the hard drives, video cards etc. Woohoo parallel processing finally comes to PC land. This is news?
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Slán leat agus go n'eirí an bóthar leat
They recently added Arthur D. Levinson, CEO of Genentech to the board of directors. It probably (hopefully) means they plan on taking science seriously.
the miicro.com site is, apparently, being slashdotted. Here is the press release at Terrasoft.com
While USB connectd fast hard drives are at best vaporware right now, FireWire hard drives are very much of a reality right now (albeit running at far less than FireWire's 400MBps limit).
By the time USB 2.0 comes out, FireWire 2.0 at 800MBps will be available (existing installations will be upwards compatible) - that is, if you want to play the "my vaporware is better than your's" game.
Most of all, FireWire 1.0 is here and supported now. USB 2.0 ain't.
Harry
Can't comment on Macs speed but when USB v 2.0 trinkets hit the shelves USB connected external hard drives will be a realistic option (they exist now but are limited by USB's current 12 Mb/sec transfer rate). USB 2.0 speeds are supposed to be 350+ Mb/sec. The big BUT in this equation is that USB is just what it's name implies, SERIAL so your SCSI chaing is going to be faster for i/o from multiple devices on the chain.
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Slán leat agus go n'eirí an bóthar leat
> if I was building a cluster of anyhing, I'd want
> to use Athlon or Alpha
...and you'd have what - hardware that runs far hotter, and gives you less performance even though it's labeled higher - great thinking.
Any particular reason you'd prefer them, besides the rote repeat of marketing buzzwords...?
> EV6 r0x0rz
Oh, look, little dogs pissing on a hydrant.
Harry
Read tha article, dummy - they are only using the motherboards.
Harry
Repeat after me, "seti@home is a signal processing application" not a scientific one! It seems to be the general consensus of a lot of people in the know (read comp.arch if you don't believe me) that altivec is a waste for general purpose scientific computing. That is why IBM isn't interested in it for their 'supercomputers'. Lack of precision and all that nonsense :> Motorola put altivec on those cpu's so their embedded customers could have a high end DSP solution not a math cruncher. The G4 makes a great high end DSP! Exactly what motorola wanted.
Yes, I know -- but idiotic jargon is idiotic jargon, no matter how many monkeys repeat it.
No Laughing Allowed!
Good one. Proof that "nonsensical technobable" == "+ moderation".
Slashdot: come for the pedantry, stay for the condescension.
Subject says it all, for once.
--
It's a
-- Danny Vermin
It doesn't make a whole lot of sense to purchase $X amount of iMacs if you plan on using only the boards.
- I don't care if they globalize against free speech. All my best free thoughts are done in my head.
It is like when I was in the music store and I told the salesman that I needed a guitar amplifier of at least 100 watts and he wanted to know why I need that much power? Because I know that I cannot afford a 1000!
DREAM LOUD!
IBM makes some very nice SMP PPC, and Linux will run on some of them. So the answer is kind of..
.sig: Now legally binding!
anybody needs a supercomputer in the living room? :)
there are better ways to spend your money... but maybe not many funnier ways
Markus.
--
Du Deutsch -> Du gehe Symlink
Uhh.
They actually do.
If you read apples page about the G4, it used to have (this is PRE dual g4 powermacs, but G4 none the less) a lot of articles there about using it in science. Like how it has the lowest Gigaflop per dollar or something IIRC.
take a look:
http://www.apple.com/powermac/
And the iMacs are developed for the cluster because they are small, netbootable, and boards can have a G4 upgrade put on them.
-Pfhor
For the last time...there is nothing in the GPL which requires a GPL'd product to be free. It just requires that you make the source available to people who purchase the product, and that you allow them to do whatever they want with such source. If you're so damn concerned about it, cough up the $389 and make "Tangent Z's clustering linux-o-rama" and put it up on a public ftp site or something.
"That's Tron. He fights for the Users."
If you really want to get what you paid for with an alpha, you have to use compaqs compiler. gcc is just not very good at optimizations on the alpha arch. There are just not enough skilled programmers working on gcc for alpha and probably PPC also for that matter. It takes years to fully optimize a compiler plus a very strange kind of person with the dedication and knowledge needed.
So, I could possibly see how MOT has some registers that are sort of doing the Intel thing... You know, the Intel Net Pipeline. The one that makes the Internet faster. Just like the Motorola DSM registers?
And it will take a LONG time before I'm convinced that your Apple iFruit can replace my Ultra Enterprise Server. I don't care if it's running BSD underneath, Apple has a LONG way to go before I'm convinced I should use an Apple product anywhere in an environment that is anywhere near mission-critical or secure.
Companies have to earn their respect. Apple has not yet made a server OS. It will take a long time of them having a good server OS for me to be convinced that I should use it.
-- Erich
Slashdot reader since 1997
>Yes, standard PC hardware is cheaper- but with
>all of the options come support nightmares and
>driver conflicts that would drive the most stable
>person into the loony bin [what in the HELL is an
>IRQ, ANYWAY?!]- yes,
1. I've supported Macs, PCs, HP/9000s and Sparcs. Mac hardware is not any less a support nightmare than PCs.
2. Driver conflicts are going to be an OS issue.
3. The whole trying hand-setting IRQs issue was taken care of with PCI.
>not only is it aesthetically pleasing
Supercomputers are typically not build to be furniture.
>[arranged in a circle, they'd look quite
>eye-catching compared to the average beige boxen]
Which would be a waste of space and complicate administration for no good reason.
The more likely configuration is a bunch of 1U machines with a KVM switch.
>yon iMac currently goes for about 800$ at the
>minimum end.
And yon $800 iMac has a 350MHz G3. Considering even the brand new shiny G4s can't match an Athlon (or god forbit an Alpha) for performance, this is just *such* a great choice. Really.
>runs on a PPC chip [WAY cooler, far more stable,
>need I go on?]
Cooler? In terms of the chip running cooler, yes. This is one thing Motorolla got right.
Stable? You're full of shit. I'm an admin at a place with over fifty PC servers. Their uptimes don't make them seem unstable at all.
>It's the cheapest reliable computer package out
>there,
Macintoshes are FAR from cheap from a price/performance ratio persepective. Not to mention that PCs are *JUST AS RELIABLE*.
Not to mention that, in order to make the things reasonably compact (yes, floor space costs money) you have to rip them apart and likely void their warranties.
>and you're never going to have to worry about
>hardware driver conflicts or a thousand other
>setup nightmares common to the PC end of things.
Kindly stop talking out of your ass. It doesn't make for a pleasant debate.
And altivec is next to worthless for most mathematical computation. It only works on single precision floats, and even then doesn't even give you a factor of two speedup, since there is (as I recall) only one altivec unit so you can't pipeline the altivec calls. On the other hand, the G4 has more floating point units than the G3, and faster ones, so it definitely would be much better.
That has GOT to be somethink funny to think about: THese eight gumdrops do more raw processing than a 1990 Cray.
The only thing that would be funnier would be to swap out motherboard diodes for LED's and seeing them flash with the data.
I used to be someone else. Now I'm someone better.
Real life is underrated.
I've heard gcc doesn't produce very well optimized code for the PPC architecture.
If this is true, what advantages does buying eight whole iMacs and throwing the cases away give over building the same thing out of an array of single board PIII computers?
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
The G4 is apple's "supercomputer on a chip." The iMac uses a G3.
Haven't I heard something about the i860 being a "Cray on a chip"? I guess old marketing tatic die hard...
do we sign up for those tests on the brains?
**Bong water Gurgle**
sidenote:Would be kinda funny to make a bong out of a Mac...New term for a "Mac Attack".
Sig it.
>Yes, standard PC hardware is cheaper- but with
>all of the options come support nightmares and
>driver conflicts that would drive the most stable
>person into the loony bin [what in the HELL is an
>IRQ, ANYWAY?!]- yes,
>1. I've supported Macs, PCs, HP/9000s and Sparcs. Mac hardware is not any less a support nightmare than PCs.
I would tend to disagree to a point. If a knowledgale Mac person sets up the Mac, then experience shows that it _should_ be cheaper to upkeep
But more often than not since the reality is that Winodws owns >80% of the market, a windows person will attempt to setup the mac and there ignorance will lead to an unstable Platform.
>2. Driver conflicts are going to be an OS issue.
Agreed. I have my share of them, but its is that next step that is important. Hit the 'net and find a _solution_ to the problem.
>3. The whole trying hand-setting IRQs issue was taken care of with PCI.
Without going off the deep end, I Completely disagree. I have a windows machine, that refuses to let the following work together:
Ethernet Card (PCI)
Modem (PCI)
Sound Card (PCI)
USB (MS Natural Keyboard)
PS/2 Mouse (Logitech Cordless Wheel)
The error reported is IRQ Conflicts. I have personally worked on this for a long time. I have consulted "experts" with windows. The problems have never been solved, so I have to hack around the problems.
Then, on top of that I tried to hook up my new digital Camera through USB. What a joke. After calling the cameras tech support, they stated that I need to isolate the IRQ for the USB device. Well that is all well and good, but I seem to be out of IRQ positions. So basically I am trying to cram 10 pounds of crap into a 5 pound bag. Nice...
>Supercomputers are typically not build to be furniture.
True. The iMac Cluster is built using Marathon Computing iRacks. So the entire thing is a big black wheeled thing. You should love it.
And yes, some of us want the computer on our desk to be "cool" looking. We do not want to feel that the thing we just spent a pile of hard earned money is relegated to _under_ the desk. We want to show it off. Let people look at it.
> Considering even the brand new shiny G4s can't match an Athlon (or god forbit an Alpha) for performance, this is just *such* a great choice. Really.
Depends on what you are testing it against. If you are doing Photoshop/DV for a living, then the G4 is BETTER than an Athlon. Tests have shown this to be true. If you are doing other things, then the Athlon would be faster.
> Macintoshes are FAR from cheap from a price/performance ratio persepective. Not to mention that PCs are *JUST AS RELIABLE*.
Again, I am paying a bit more for two things, both of which I prioritize over raw speed. I am paying for a Nice looking Box and an User Interface that is both pleasing to my eye and logical for _me_ to use. Considering My PC does not seem to want to work well at all, then I would have to disagree with the second part of your Sentence.
>Not to mention that, in order to make the things reasonably compact (yes, floor space costs money) you have to rip them apart and likely void their warranties.
Yup, the APPLE warranty is toast, BUT Terra Soft provides their own warranty for the cluster.
> Kindly stop talking out of your ass. It doesn't make for a pleasant debate.
Remember, other peoples Milage may vary from yours. Feel free to debate. Point out problems with the post. State your case, but when you make wide sweeping statements be able to back them up with Facts not religous war type hype crap.
How do they get the interconnect working on this setup... Is it using a fibre channel SAN or something FW based?
Those new cubes are proof enough that you can cram lots of PowerPC hardware into a really tiny space (without lots of fans, either). Furthermore, Altivec should make the G4 absolutely CRUSH any G3 in mathematical computation, even the ones with a meg of cache.
Of course, if I was building a cluster of anyhing, I'd want to use Athlon or Alpha -- EV6 r0x0rz...
--
"A witty saying proves nothing" - Voltaire
First off, I'm sorry, but there probably isn't a cool selection of translucent cases to choose from. They mention using eight i-mac logic boards, not eight entire i-macs.
Details are a little short - the article says that it's all in the same box, which implies that there is a high-speed interconnect. I hope that isn't the ethernet port on each of the i-macs.
What's so special? They're doing parallel programming against a few (almost) machines? Parallel programming types have been doing this for years, and there are highly developed libraries to help synchronize and send data to independent machines across a network which are participating in a parallel computation.
This is going to start a craze of little kids gutting their i-macs to make a super computer with all of the other little kids in the neighborhood. Be the first on your block!
If apple needed to guard the G4 with tanks, then this thing must explain why the star wars missile system is being revamped - to protect it!
Drag n' Drop DVD Recommendations
Why stop at lifesavers? I want baskin robbins. Computers in 31 flavors.
when Push Comes to Shove
It looks like they are only using the logic boards in these things not the whole damn system, so yer not going to see different gummy colors. Yeah, I know that was probably a flip remark, but it seems as though most /. editors don't bother reading these links anymore either.
Has anyone looked inside the iMacs? Not much there except the monitor. You could probably fit 4 of the logic boards into the space of one G4 server.
blah
clif
Uhh, not sure where you heard that. We haven't heard anything from Apple Legal.
Regards,
Dan Burcaw
dburcaw@terraplex.com
Terra Soft Solutions, Inc.
Naw.... we should call this cluster iSkittles. iSkittles: Process the Rainbow.
--
Intelligence is definitely a recessive trait.
Terra Soft Solutions are, AFAICT, concerned with quality and responsibility in their work, as well as making an operating profit.
Build a parallel cluster at home. Get it to work. Now think about supporting it for a range of uses and users. Now add up the cost again.
- Derwen
http://fsfeurope.org/
He deserves +mod points for "creativity in trolling".
I especially liked "front-port hyperoptic coaxial" and "FTTC tech ... to be used in small, CAT5-based RCN clusters".
11*43+456^2
yer.. cause all that competition from different vendors driving the price down just pisses me off.
How we know is more important than what we know.
On a dvorak keyboard, N and S are next to each other. Never attribute to ignorance which can be attributed to typos.
-- boredwithmysig
Is it just me or is an iMac not the most logical computer to cluster. What a waist of 7 monitors, 7 CD drives, 7 flopp... ok no floppies but still.
This might be a little off topic, but I was wondering if anyone has attempted to dump Linux on one of those cute little Mac Cubes and use it as a server or workstation. Think of the space it would save....
You don't need a weatherman to know which way the wind blows.
You can get a dual 450Mhz G4 with gigabit ethernet for less than US$2500 even from the Apple on-line store - and if you could dump the DVD drive you could do even better. (It's +US$300 for dual 500s.)
That's about the cost of two iMacs with a better ethernet, better FPU and the addition of Altivec engine.
Of course alot of that advantage is assuming your OS and solutions are able/written to take advantage of Altivec^H^H^H^H^H^H^H Velocity Engine vectorization. Although the added FPU performance will benefit about any scientific inquiry and the ethernet is mostly an advantage to problems that require intensive CPU->CPU communications.
But in reality the forth coming Mac OS X should be the best solution for this set-up. It has full featured SMP for the OS, complete protocols for apps to access SMP and Altivec accleration for many of the OS operations with Mach/BSD threads running undernaeth it.
NEXT had distributed processing/clustering protocols. If the distributed/clustering make it in to the first release of OS X it should be the perfect solution for this kind of thing.
=tkk
P.S. Of course if low-end 11MB ethernet is good enough for your problems you could add Airport cards and have a covert/wireless supercomputer without anyone in your office knowing it! ;)
Bill Gates - Creationist?!?
What happens to all the cases and monitors? I presume they're not getting the logic boards from Apple, as their press release makes no mention of this, so they must be buying them in bulk and stripping them... And why does having the cluster next to you make development easier? Why a need for portability? Don't you just log in remote and run your program? Calum
The big question is when Apple will build and ship the iRack. Imagine -- a stack of 1U or 2U G4 systems, all running Darwin and MPI...
Hell, now that I think of it, Apple doesn't even have to do that themselves, now do they?
/Brian
If you hook 8 Macs into a token ring, would you consider that a Fruit Loop?
"..don't you eat that yellow snow."
On the other hand, it won't be long before FTTC technology becomes cheap -- and stable -- enough to be used in small, CAT5-based RCN clusters. I'd expect this kind of cluster to break the $18k price point mentioned in the article by the end of the first half of 2001.
If these guys had just waited until the iMac's come out with G4's, they're job would have been much easier. The G4 contains six new registers separated by semaphores that control locking of memory locations across a network (IP v6 compatible). These aren't available under the Mac OS 9, because it doesn't use the memory protection available from a UNIX-like OS. Mac OS X will support this, hwoever, along with a new release of WebObjects, positioning Apple as a leading e-commerce platform provider with Sun and IBM. Apparently, many users of the Mac OS have been pestering Motorola to add this into hardware. I predict it is unlikely to be in Linux in the next few months. With the current lack of multi-pipeline support in the kernel, it will take several man-months of effort to work this properly. Several architectures have been proposed, I favor a regimented memory access (RMA) style.
what in the HELL is an IRQ, ANYWAY?!
Right... {yawn} The tired old argument about how much easier it is for the layman to deal with Mac hardware. Great marketing hype for people like my old man. Now go ask him why he can't use his Mac printer with his Mac.
Umm... constantly?
Yeah, aesthetics are so important in computing. You really like that marketing stuff, huh?
If you look up and to the left of your 'n' key, you'll find an 's' key. I hope it's not broken? Open your eyen and use the right lettern.
by many... what? marketing drones? geese? fruit flies?
You might try a version of reality that isn't so tainted with Mac marketing hype, it might help you provide better input in a technical forum such as this. Or maybe not... As the song says, "There's always a joker, that's the rule, as foolish as he can be..."
No Laughing Allowed!
"The new iMac cluster is infinitely expandable..."
"Because there's always room for JELL-O!"
Where's Bill Cosby when you need him?
---
pb Reply or e-mail; don't vaguely moderate.
pb Reply or e-mail; don't vaguely moderate.
means Interrupt Request. Correct usage of this term is left as an exercise for the reader.
Not that I don't like some Macs, but I'll take my cheaper PC hardware over a pricey G4 any day.
And why is it everyone refers to cases as beige? Cases come in a variety of colors today, from off-white to black to iMac-ripoff. If you want your PC to look like a mentally retarded UFO, you can.
***
Well, from the experiences I ahve had recently, g4's are mean mean mean scientific machines. We have quite a few floating around the national lab where I work. The PC/MAC team is going head to head with the Unix team on Seti@Home. I was holding the top spot with my dual p3's chewing up chunks. Then in comes these G4's..they are averaging about 5 hours per processor on a block. That's really quite good. Of course, we countered with the PA-RISC machine that could do 24 an hour ;)
But the fact of the matter is that their performance is prompting us to look at g4 clusters as a scientific computing solution. Go figure. I wonder if Apple will buy into it..their machines as scientific boxes ;)
-- Who is the bigger fool? The fool or the fool who follows him? --
Yes, we've finally found a reason for the mulitude of iMac colors. Too make funny-colored clusters. Works for me!
see the subject.
>But more often than not since the reality is that
:P)
:)
>Winodws owns >80% of the market, a windows person
>will attempt to setup the mac and there ignorance
>will lead to an unstable Platform.
And more often that not, Apple claims that you the only setup their machine needs is to plug it in and turn it on. (There is no step three!
Given that they market their platform as ideal to ignorant users, and most Mac zealots tout the fact that you don't need to be skilled to set one up, this claim seems VERY suspect.
Not to mention that my support days were spent supporting VARs, many of whom had only ever sold Macintosh.
>The error reported is IRQ Conflicts. I have
>personally worked on this for a long time. I have
>consulted "experts" with windows. The problems
>have never been solved, so I have to hack around
>the problems.
Congratulations. You're a rare case. I spent a year and a half on the general PC support line and got only ONE call with an IRQ conflict, out of around 80-100 a day.
Given the list of hardware, I'd guess its either an OS issue, a BIOS issue or broken hardware, rather than a dearth of interrupts.
>Then, on top of that I tried to hook up my new
>digital Camera through USB. What a joke. After
>calling the cameras tech support, they stated
>that I need to isolate the IRQ for the USB
>device. Well that is all well and good, but
>I seem to be out of IRQ positions. So basically I
>am trying to cram 10 pounds of crap into a 5
>pound bag. Nice...
Tech support being stupid is not a fault of PC hardware. One of the advantages of USB is that only the controller needs an interupt, not the device.
>And yes, some of us want the computer on our desk
>to be "cool" looking. We do not want to feel that
>the thing we just spent a pile of hard earned
>money is relegated to _under_ the desk. We want
>to show it off. Let people look at it.
Yes, but a supercomputer is hardly a desktop.
>Depends on what you are testing it against. If
>you are doing Photoshop/DV for a living, then the
>G4 is BETTER than an Athlon. Tests have shown
>this to be true. If you are doing other things,
>then the Athlon would be faster.
And those tests are of a piece of software which lacks optimization for the Athlon.
Given that we're dealing with a platform being used to run custom scientific applications though, it can be tuned for either processor.
Tests which bench optimized code vs optimized code show the Athlon to provide MUCH better performance at each processors current clock speeds.
>Again, I am paying a bit more for two things,
>both of which I prioritize over raw speed. I am
>paying for a Nice looking Box and an User
>Interface that is both pleasing to my eye and
>logical for _me_ to use.
When building a cluster, you'd be a fool to pay for a 'Nice Looking Box' over raw speed. The point of a Beowulf cluster is performance.
Likewise, the interface is a non point, as you will not be using these machines directly. If you want, build the control software on MacOS and have a ball.
>Considering My PC does not seem to want to work
>well at all, then I would have to disagree with
>the second part of your Sentence.
Your broken PC does not invalidate my experience with thousands of users and hundreds of PCs.
>Remember, other peoples Milage may vary from
>yours. Feel free to debate. Point out problems
>with the post. State your case, but when you make
>wide sweeping statements be able to back them up
>with Facts not religous war type hype crap.
Funny, thats what I thought I was responding to.
haha...gummysevers, running linux...
hehe...hrmmm...8 $1,500 gummyservers running linux
hrmm...uhhh..8 $1,500 gummyservers running a free OS
uhhh...ummm...$12,000 worth of gummiservers
ummm...$18,000 - $12,000 != 0
well, hrmm...that's interesting...I guess maybe with cusomization, and stuff like that.. i dunno...
probably off-topic...
MODERATE DOWN
Check out my sysadmin blog!
This is by no means intended to start a flame war, but iMacs?!?
/watt part right, but that's about it.
I've actually seen a few, and I've even worked (albeit very little) in Photoshop on one, and I must say that I'm not impressed with their performance at all. My dual Celery is by far faster then the iMac I used, and roughly for the same price... But for the same amount of money, I have a _lot_ more ram, better v-card, etc. So where is the "better competitive price/ performance/ watt ratio?" Maybe they have the
Not to mention that they are by no means upgradeable (try plugging in a DVD, a CD writer _and_ a Zip drive into an iMac all at the same time). And if anyone is going to mention USB, I really don't think USB comes close to even the cheapest Adaptec Ultra SCSI card w/ SCSI disks on it.
The only reason that I can find for this application of iMacs is publicity. Nobody has even thought of doing this before (and why would they?), so it has to make news. And that's fine by me I guess. I'm just very curious who is going to buy such a thing.
I forgot to sign up.
but something shall be released.
when Push Comes to Shove
You can get 8 iMacs for less than $8K.
Yes, standard PC hardware is cheaper- but with all of the options come support nightmares and driver conflicts that would drive the most stable person into the loony bin [what in the HELL is an IRQ, ANYWAY?!]- yes, it's more upgradeable and you have more choices, but after the initial build, how often do you switch things around?
Linux in cluster mode on a bunch of iMacs is a great idea- not only is it aesthetically pleasing [arranged in a circle, they'd look quite eye-catching compared to the average beige boxen], yon iMac currently goes for about 800$ at the minimum end. That's eight hundred bucks for a machine with four external parts [box, power cord, keyboard, mouse], runs on a PPC chip [WAY cooler, far more stable, need I go on?], is a quick setup and, at the bottom end, is running Linux on Apple hardware, ackowledged by many as some of the best parts out there.
It's the cheapest reliable computer package out there, and you're never going to have to worry about hardware driver conflicts or a thousand other setup nightmares common to the PC end of things. - but good luck keeping those CDR drives closed! The iMac is great for this: it doesn't NEED a big screen, and the machines really, honestly, suck ass as kiosks without extensive internal surgery [which is really not easy to do, I can tell you that!]
Huzzah. Now someone who can code needs to port more *nix apps to PPC architecture- I'd be running linux right now were it for a few minor details such as that.
Sure it runs linix, but its not like they are the first group to do something like this. Project Appleseed is over 2 years old... http://exodus.physics.ucla.edu/appleseed/appleseed .html