OpenStreetMap
Today, I've learned, there's an mapping app for the open-source cellphone OpenMoko Freerunner, using the OSM data: http://www.tangogps.org/gps/cat/News
It's able to fetch missing map data in the background. They've a Youtube video, too: http://www.tangogps.org/gps/articles/5-Video.html#extended.
The software also runs on the EEE PC.
I can't wait getting my Freerunner... ;-)
Discussion
Comment from OJW on 10 June 2008 at 13:41
There is also Pyroute being developed for use on Freerunner:
http://wiki.openstreetmap.org/index.php/Pyroute
Comment from schlesi on 10 June 2008 at 17:37
I know pyroute, but didn't know, it's being ported for the Freerunner, too. Freedom of choice ;-)
Comment from bernd_herd on 25 June 2008 at 20:51
There is an application available to run on Java-Enabled mobile phones that displays openstreetmap data and supports routing with openstreetmap data for start and end point in germany. The route is computed by an internet server http://www.openrouteservice.org/ and displayed on the phone. See http://beta.arktosmobile.de/aosm/