Very nice coin!
I visited a cache in Namur, Belgium one month ago:
A cache of Seashell Road
The seashells on the ground guide the way to the great ancient scenery.
BeeLineGPS for PPC can do Waypoint averaging to get high precision when mark a cache point:
http://www.visualgps.net/BeeLineGPS/default.htm
Is there any similar software on Symbian S60?