exact same thing is used by Kaseya to track down stolen laptops.

I like the idea of this thread! I myself am not a skilled code writer or graphic designer or anything but willing to help with the ideas.

Few has talked about SMS and GPS. Sending an SMS when SIM is beeing replaced (differs from the list provided) is a great idea. And it should send some information about the phone with it. For example the GPS coordinates, how much battery left, some sort of code with which you can set on the alarm by SMS like danx suggested (which is a great idea) etc.It could also send all of this into your e-mail if networks are available.

How about also some app that would send GPS coordinates into your e-mail, SMS or in some other place every hour or so? Of course if networks are available (e-mail). That way you could keep track where the phone is.

One interesting thing might be also a bit modified idea about the ringtone (or alarm) that would say "This phone is stolen, please call 'some contact number'!". So when someone is calling for the thief (ringtone), the thief is calling or doing some other thing which has been adjusted, it would trigger the phone to play that audiofile and lock the device. Only way to shut the audio would be typing a code. You couldn't even shut down the device without the code.

Of course everything related to encrypting your data, sending them into some secure place and deleting them would have been done right in the beginning.

Ok, we have to think as thieve then, first thing is a change sim card definetly, next play with it for while, find some games, etc., and after got bored to finally privatize it by flashing it with a fresh firmware.
So we have limited time here to lock it down, hardly, until thieve flashs it.

well anything that stops them turning it off would just result in the battery being removed, there goes your chances of recovery! better to allow them to turn it off, but a script in the shutdown process sets the alarm for ten minutes and auto-reboots the phone, perhaps even reboot it an a way that it still appears off, yet continues to transmit gps etc.

love this, but perhaps they could get under the ground, bunker sort of, where no one would hear how pity n900 screaming, and then they find button 'u' on it, and hold it for 5 secs and finally hook it to a big bro who will do the flash job.

Guys also let the app send the new SIM number thru SMS .... and if available let it send other related information.

Also could be implemented after SIM was changed a nice form asking for basic "new-"user information like, full name, home number, related number if phone is lost^^, address etc etc... this will very usefull information when trying to recover it.

the auto-reboots appearing off idea is really great. but never again let it back to normal, keep the look of being turned off also it will save energy.

It is good let take pics using the front camera when the thief slide on the keyboard.

some1 pls summarize all the ideas. TIA

They'd have to put the battery back in eventually to use the device. And if you put a script into the boot process then the script will automatically come back once the system is back on. For example, this

http://blog.tersmitten.nl/archives/873

Updates DyDNS whenever a new internet connection is made.

Anyway, although most thieves could eventually figure out how to reflash this device, it isn't a very simple process. The N900 is a pretty unfriendly device for anybody expecting an iPhone or Android's user friendliness.

What I wonder is if a person puts a SIM in that doesn't have a data plan, will an internet connection still work even if they don't pay for it or have it on a plan.

I still love the idea of this app - a shame that the I am here app disappeared into the ether.

what about studying i am here? it has got pretty much everything needed... (sends some data to suspicious email though)

so settings can be changed with correct sms etc.... so everything is either periodical or can be triggered with sms.

theres an app that lets n900 automatically connect to free wifis