I just see that there is a open source map project:
http://www.openstreetmap.org/
It is possible to download maps:
http://wiki.openstreetmap.org/index.php/Planet.osm
And there is a linux viewer (if I am not wrong here):
http://packages.ubuntu.com/de/source/hardy/gosmore
Now it would be wonderful to have maps on the DR1000
Gogolo