UPDATE: I’ve posted a more comprehensive set of resources for free topo maps for Garmin GPS receivers.
One of the great things about Garmin units is the wide range of free maps that are out there for them. I recently became aware of another source, this one offering 40-foot contour interval maps of Colorado and Wyoming. The not quite accurately named site, Miscjunk, will soon add Utah to the mix too.
The screen shot at right shows a sample map loaded onto the new Garmin Colorado series. If you load a custom (U.S.) map onto the unit and have Topo U.S. 2008 (which has DEM data) loaded too, you’ll get the nice shading effects seen here.
The site also features Minnesota ORV trails and Colorado 4WD trails.
Many thanks to the mysterious "dfg" for the great maps! Oh, and while
the maps are free, there is a donate button on the website’s map pages, giving you an opportunity to say thank you and support the effort to produce more maps.