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I've written a little Android app that updates a webpage with your location. I've thought that people with an expensive sports car might like to use it by leaving it in their glove box when their car is serviced, and seeing if the garage takes it on a "Ferris Bueller" style jaunt around town.

1. Telephone companies can and do routinely trangulate from towers or use GPS-enabled smartphones to establish the position of a cellular phone. It's not rocket science to integrate those measurements over time and obtain the velocity of a cellular phone.

I used to work in the R+D department of a large mobile phone company. Most of you will have heard of it.
I had access to the internal location API system, and I wrote various experimental projects using the data. Had some very good ideas there, but the business wasn't interested in taking any of them up.

I'm not saying it's purely because I had a Subaru Impreza at the time, but I was curious to know if the cell triangulation data was good enough to be able to work out what speed someone was traveling at, so I wrote a system that logged my location every 15 minutes, and tried to determine it.
Basically, it's not possible. The accuracy of the triangulation methods isn't good enough, you don't switch triangulated points often enough, and roads have bends in them, so you travel less in a straight line in 15 mins than you traveled in reality.
It's possible, if you drove on a straight road at 100mph for a hour, obviously, but what with roadworks, traffic jams, bends, cameras and the size of the UK, it's not likely. :) I don't have access to those systems any more, so I've had to resort to GPS tracking myself now - and that is accurate enough. Lucky I take the bus to work now, and am hence relaxed enough when I'm driving to just potter along.

But cell tower triangulation - no, not really. If you're worried, worry about carrying round a transmitter with built in GPS - I would be very surprised if the phone companies/manufacturers didn't have back-doors to remotely activate anything on your phone - GPS, microphone, etc.

Run Firefox as another user. Won't save your passwords, but it'll save your files. http://calum.org/posts/running-firefox-as-another-user-using-sudo

I am looking at it the other way around. There is not really any reasons now to require root access in order to listen on ports below 1024.

Amen. I'm glad I'm not the only one. In this day and age, where anyone can run a Unix box, the whole "root under 1024" thing is redundant. http://calum.org/posts/root-to-bind-to-ports-under-1024.

Make it a damn kernel config option at the very least, and let me decide.

I wrote such a system many years ago. You can see it here.

I'll be driving at 12:30 UK time ( 3 hours), so you can watch me move.

Good point. When you've got 30 or 40 pounds to lose, 12 weeks of moderate exercise isn't going to cut it.

Without sounding like an advert, try the Cambridge Diet. Kicks your body into ketosis, and the weight falls off. Really small amounts of food can kick you out of ketosis though, so you have to be very strict. I wrote about my experiences.

You're right that it's a "clear shot" through the atmosphere, only about 70 miles away. However, the ISS has a very large footprint, and so you're competing against hundreds or thousands of other amateurs in the 3000 mile footprint. Plus, you'd be talking to fucking astronauts! :) I don't know many people who can say they've spoke to people in space. I'm sure that once I manage it, I'll move on to other things - that's the good thing about Amateur Radio - there are so many different facets to try. At the moment though, I only have a car to operate from, and only have an omni-directional antenna - which wastes about 99.99% of my output power. So I'm at a huge loss.

I realized I'd rather go places than just have my phone tell people I'm at home...still.

That's what we sensible people call a false dichotomy. You can do both, you know. (Although I have never remembered to take it other than to the Netherlands one time.)

Write your own. http://calum.org/location/. I worked for a mobile telco until recently, so had access to the location info direct, but now I just run a GPS app on my phone, and it's much the same.

Damnit Richard, man! I was calling you as you passed over the UK, but you never answered. People think I'm mad when I'm looking into the sky, saying I'm trying to talk with spacemen.

I mentioned this above, but I wanted such a system for myself, so I wrote one that runs on Java enabled phones. mobfob.calum.org. Works well enough. The cryptographic hashing is just an MD5 sum, but if you don't know the key, you can't predict the hash. I just want to find someone who can write a PAM module so that it can be hooked into SSH, /bin/login, etc.

I wrote a little Java app for phones that works in the same way as RSAs SecureID. I'm trying to find someone who can write a PAM module for the server side now, so that after you've logged in with your username and password over SSH, it prompts you for the current token.

This is actually why I started my Location Tracking system a few years ago.
Convince enough people to submit their data (pay them for it, per mile?) and then sell the aggregated data to people who wanted it. Road builders, government, people who want to know where congestion is.

New spots are beginning to break out on the face of the Sun and may signal the end of a dry spell in solar activity.

For which I, as a radio amateur will be very happy, as we're currently right at the lowest point of the sunspot cycle . The sun's activity correlates with the "reflectivity" of the layers of the atmosphere. When the layers are "reflective", signals can bounce, with each bounce landing a thousand or so miles away. If you get a few bounces, you can talk to the other side of the world, even on low power. When there's no propagation, you are unlikely to get more than 50 or so miles (groundwave), no matter how much power you pump out (excluding modes like satellite, moonbounce, meteorscatter, etc).

Although the solar dials don't seem to indicate it.

I concur. I cringe big-style when I see a van going past with their email address of joes-plumbing@aol.com, or bills-whatever@hotmail.com. It just screams unprofessional. A .co.uk domain is about £2 per year.
Gmail is a bit better though. And in the UK, you can see who are the early ones, as all UK Gmail signups now are googlemail.com.
/me had mine when it was invite only. Still like running my own mail server though. Datacentre + server + Postfix + Courier IMAP + bunch of anti-spam things, and it's all good.

Sort of on-topic: I'd just like to say that recently I decided to code a Java app for Smartphones that is a token generator (MD5 of minutes since 1970 and known string appended) - it works pretty well. I'm sure all you bastards will find some flaws in it though.

http://calum.org/posts/running-firefox-as-another-user-using-sudo is a very good idea.

A bunch more here :)

You know what that means then? That I could be incriminating myself*. Although I don't speed any more due to the very high fuel costs. £1.30 per litre of diesel. Meh.

However, I don't transmit the timestamp of the signal from my phone to the server, so I could always argue that network jitter, etc caused inaccuracies.

Actually, seeing if cell-triangulation was accurate enough to measure speeds over long journeys was the reason I started with this. Now of course, I've "upgraded" it to GPS.

And all the others you could possibly want! "Give a woman a fish and you'll be sleeping on the couch again."

Do as I do, and run Firefox as another user.. Then all it can read is stuff I've saved from the web, and cache, cookies, etc. Not great, but not as bad as being able to read my normal user's data.

Wrong. It's generally from about 300 metres in cities to 1-4 miles in rural areas. And it's not that accurate. It's just the point in the middle of the towers that your phone can "see". Check out http://calum.org/location/ - it uses both methods. GPS when I'm running the GPS app on my phone, and cell-triangulation at other times. Currently, it says I'm at 51.452371,-2.618589 +/-372 metres. Good, but not that good. Plus you only update when you make/receive a call/text/data session, switch the phone on/off, change cells, or every 90 mins otherwise. Way inaccurate for tracking cars.

Another idea I had years ago. My idea though was to pay people to run the software on their phones (just as Google pay people to have ads on their sites - paying per hour of data uploaded, or something similar), and then lease the aggregated data to interested parties. Companies interested in building/buying toll roads, government agencies to see if new roads need to be built, etc etc.
However, with SatNav getting more and more sophisticated, it was only going to be a matter of time before TomTom (or whoever) built a model where it uploaded your position back to them, enabling them to build up a realtime picture of traffic speeds, which they could then use to update drivers to avoid jams, etc.

And the other point - why use two browsers? On a multi-user operating system, just run them as different users.
I wonder how long it will be until, when you create a user account, a second one (or two or three) is automatically created, and potentially vulnerable apps (browser, mail, etc) configured to run as separate users.

Or, if you have a DVB card: mplayer dvb://BBC\ ONE -dumpstream, and you get the pure MP2 that your TV sees. You can them encode it down to whatever you like.
I've set up an email address that calls a script which takes the start time, duration, and channel name from the subject of the email, and schedules a cron job for that. Voila. I'm on the other side of the world, and I forgot that I wanted to record Peep Show? (Not from the Beeb, but..) A simple email from anywhere does it.

Or, if you have a DVB card: mplayer dvb://BBC\ ONE -dumpstream, and you get the pure MP2 that your TV sees. You can them encode it down to whatever you like.
I've set up an email address that calls a script which takes the start time, duration, and channel name from the subject of the email, and schedules a cron job for that. Voila. I'm on the other side of the world, and I forgot that I wanted to record Peep Show? (Not from the Beeb, but..) A simple email from anywhere does it.

My home-brew GPS tracker (that runs on my Nokia 95) is very inaccurate. I have to calculate the speed by working out the distance between the lat/lon now, and the lat/lon last time. Bearing in mind I sometimes only get readings +/- 300 metres, it can show me doing 300 mph. And in a wanked old Peugeot diesel, that's not right.
I'm sure that a dedicated GPS device can devote a lot more chip-space to getting accurate signals though than a phone that does everything.

Arse. Try again.

I had this idea ages ago. Privacy and Big Brother issues notwithstanding, it makes perfect sense. If the average speed of cars on the M4 Westbound at Chippenham is < 10 mph, then possibly look at re-routing drivers a different way. It's what I wrote my tracker with in mind. (Although I don't know anywhere I can get access to a free route calculating API though).

Even on Linux where you run as a non-root user, think about running Firefox as another user.

Like I've been doing for a while now.
I'm not going to go anywhere tonight, so if you want to see it in action (it's quite cool :) ) put your email in the notify box, and hit "Let me know!" to get a one-off email when I start moving.

calum.org
The first thing I notice is that the colour scheme. It's well-designed aesthetically(though very bright), but it is low-contrast; it's not very easy to read the blue/grey text on a bluish background. Furthermore, the design makes presumptions about font size and so breaks for me with my default font size(I'm myopic and I like to read the screen from a distance).

Still, I allow my eyes a few moments to adjust to the colours, lower the font size(moving closer to the screen) and move on.

I'm easily able to subconsciously identify the main elements of the screen: a menu on the top, a bit of info on the left, a login pane on the right, and the familiar list of blog posts in the middle.

After a few seconds, I've identified what this site is(a personal blog) and how I can use it("Read more" links and "Add comment" links). I'm comfortable enough with the layout to use it.

Now, this is my brain on your site:

First thought: as the other mentions, the colour scheme is frankly reminiscent of a "shady" site. (By this I mean an "underground" site - such as those used in the field of software piracy before it became cool. Irrational though it may be, my second thought is that I'm in agreement with the guy who said he wouldn't install anything from that sort of site. (Frankly, I didn't even want to enable Javascript.)

Of course, the second visual impression is the huge box which tries to force me("This message will not disapear [sic] until...") to enable scripting. I don't, because this site has already demonstrated that it's willing to annoy me, and I know there are plenty of opportunities for further annoyance if I enable JavaScript. (By the way, I'm used to NoScript: if your menu links don't work without JavaScript, I don't get mad as hell and won't take it anymore and bother you about it, I enable JavaScript temporarily to make it work, as long as the site looks reasonably trustworthy. A non-intrusive, informative message helps(it especially would if I wasn't already familiar with the situation); an attempt at forcing me is counter-productive.)

Now, I get to admire the site from afar. There's a garish purple "smoke" background graphic which makes the header text hard to read. The text is high-contrast, but the colour choices are, as mentioned, positively offensive.

There's mention of music: boy are you glad I had NoScript enabled, or this would be a lot more negative. I do not want music to play in my web browser without my explicit consent, and I suspect no-one else has appreciated this trick in the last seven years.)

First impressions are over: this is the point where I'd leave the site in disgust(and did, before I decided to go back and post a more thorough review to explain the point of view of the other commenters). I've failed to understand what the website is for(my best guess at this point is "something drug-related" due to the psychedelic experience), and I have absolutely no desire to interact further with it.

Instead, I come back and turn my attention to the menu on the right. Scratch that, that's not actually a menu; it's a collection of random web-related things. (The most useless, apart from the ever-hopeful webmaster's suggestion that I donate money (up to 5,000 USD) to the creator of this monstrosity, is the ability to validate the pag

Want to track yourself for the world to see?

At least as another user.

A good way to reduce the possibility of malware affecting you in Linux is to run your browser as another user. It's easy to set-up, almost pain free, and means that, barring local root exploits, it can't delete/alter your data, modify your login scripts etc.

I'm sure it's possible to do in Windows - runas firefox.exe - but I haven't tried it.

And now phones come with GPS built in, it would only take a little Java app, a website, and some AJAX to glue it all together.

I don't want another Ericcson since Sony bought them. Had a P800, and a P910i (and maybe a P900?), but I'm a Nokia man all the way now. N80ie for me, and N95 from work. Good stuff. This page shows where I am via GPS, falling back to cell triangulation if I'm not running the app. Quite nifty.

Bah. This is exactly what I was trying to do. Lots of road users, all updating a central server with road speeds, and the ability to smartly reroute people based on knowledge of delays, etc.

I shouldn't think it'll be long, now that people have phones (IP connection) with GPS built-in. It's not much further until end users are offered a cut in the monthly costs in exchange for providing data of their movements.
Of course, the security/privacy implications are something that need to be carefully worked out - TLS protected location updates, and no identifiable information would be a good starting point.

The only things that need be passed along are current GPS location ( deliberately imprecise by about 20ft ), current velocity ( deliberately imprecise by about 10mph ), last 5 secs acceleration on all 3 axes and a time stamp.

That's exactly what I do. Except I round off the GPS lon/lat to a certain amount of decimal points - that basically makes it inaccurate enough not to incriminate me - and I don't bother with a timestamp - saves on bytes - I just use the time at the server when it's received.

Mitchell, and Webb, for the non-UKians here do a very funny show called Peep Show which I only found out a few months ago, and have been raving about ever since!

I've been tracking my location with this technology, and making it available on my webpage for years. It's not accurate enough to determine the speed you are travelling though (I made sure of this first!).

I have access to my own phone's location data, and I (apart from doing all sort of other funky stuff with it) set up a system to measure my speed.
It didn't work well.
First, I could only poll it every 15 minutes. Secondly, cells overlap. Thirdly, it just gives you a triangulation based on which towers you can see.
So basically, on a drive to London along the M4, I stuck at exactly 70mph for the test, and it showed me doing everything from 59 to about 84, with one sector at 97. It's not accurate enough. Until the 3G phones come along.
And you can see where I am (or rather where my work phone is (which is on the desk next to me)) now on my homepage....

I track my phone on my website.

Oooh! Ooooh! AJAX reference. That means I can legitimately mention my AJAX message board and viewer counter, that's to be found at calum.org!

Please try it out before you mod me. It's not bad, if I do say so myself.

I bought an iRiver IFP 899 purely because it said it supported Ogg Vorbis. However, I'm at a loss to get most of my files to play on it. Apparently, things have to be encoded at a minimum of 96k/s and a max of 224. But even supplying oggenc with those parameters, it still can't play them.
/me shakes fist at iRiver.

iRiver IFP 899

I'm still waiting for my site, Calum to get indexed. The bots come regularly, but nothing in there. If people could just paste the following link onto their pages, Calum, I'm sure everything would be right with Calum and Google. I'm sure Google doesn't hate Calum, and that there is just some misunderstanding.
:)

I'm still waiting for my site, Calum to get indexed. The bots come regularly, but nothing in there. If people could just paste the following link onto their pages, Calum, I'm sure everything would be right with Calum and Google. I'm sure Google doesn't hate Calum, and that there is just some misunderstanding.
:)

I'm still waiting for my site, Calum to get indexed. The bots come regularly, but nothing in there. If people could just paste the following link onto their pages, Calum, I'm sure everything would be right with Calum and Google. I'm sure Google doesn't hate Calum, and that there is just some misunderstanding.
:)

I'm still waiting for my site, Calum to get indexed. The bots come regularly, but nothing in there. If people could just paste the following link onto their pages, Calum, I'm sure everything would be right with Calum and Google. I'm sure Google doesn't hate Calum, and that there is just some misunderstanding.
:)