Good post. My Garmin 60CSx can use all the standard formats: degrees.decimal degrees, degrees minutes.decimal minutes, degree minutes seconds.decimal seconds, UTM and a whole bunch of what appear to be regional specific formats. It's just math.

As for landmarks, one of the things I did with the GPS kept in my survival vest is to load a number of the local aircraft navaids (TACAN and VOR) into my GPS as waypoints. It makes it easy to communicate bearing and range from a navigational reference available thru a pilot's instrument panel.