Sort of a networked GPS/routing thing with route sharing built in and calculation of routes offloaded to a central server or something?
I hope the project offers a lot of features with a great interface, because price=0 as in the navigation products below is hard to beat. All you need is a GPS-enabled modern-ish phone. Or a bluetooth/serial GPS module it can talk to.
With that whole web 2.0 social stuff and route/place/map sharing:
http://www.nav4all.com/site2/www.nav4all.com/index.php
Without:
http://www.amazegps.com/welcome.php
I've used nav4all for more than a year now, and it has never steered me wrong in any place I have found myself in.