OutdoorActive maps for Austria, Germany and South Tyrol work as well. They are quite detailed and include lots of hiking and biking trails.

OutdoorActive.com (Germany only)
http://t0.outdooractive.com/portal/map/%0d/%d/%d.png

OutdoorActive.com (Austria only)
http://t0.outdooractive.com/austria/map/%0d/%d/%d.png

OutdoorActive.com (South Tyrol only)
http://t0.outdooractive.com/suedtirol/map/%0d/%d/%d.png

Thanks to http://gc-livepedia.de/wiki/Map_servers for pointing these out.