A few years ago I've had an abonement of a magazine about robots. You've got parts of a robot with every issue. And after a while you had a driving robot. It looked like this:

Now I've reused the basis of this robot with the motordriver and connected it to an atmega16-16pu. A mobilephone is receiving commands from the internet (over GPRS) and sending them to the microcontroller. The software on the other side of the internetconnection is programmed in purebasic.
Video of the software
AVI: http://www.bradan.eu/files/robot.avi
Youtube: http://www.youtube.com/watch?v=xzdBMKklsPs
Webinterface (Also coded with PureBasic)
http://www.bradan.eu/files/robotweb.jpg
The software for the mobilephone is written in java and the software for the microcontroller is written in C



 . The signal is in a range of -20..20mV or such and the µC can't differ it very well from the noise. So now I've got 3 bits per second.
 . The signal is in a range of -20..20mV or such and the µC can't differ it very well from the noise. So now I've got 3 bits per second.

