Anyway, this thread is great food for thought.
I know that some GPS devices can log your traveled route and then upload it to your computer so you can see your path on Google Maps or something like that. How does it upload the path to your computer tho?? ... thru USB? ... thru Wi-Fi? ... thru Satellite to some server on the Net and then to your computer?
I'm thinking that you'd need a device with GPS and Wi-Fi (or preferably cellular, if you were a big baller like that)... and then put it in a huge seat with a big battery. GPS does drain batteries... I know that much.