Rock & Crystal
Rock & Crystal (and Pebble, too) are a geocaching family in Paradise, California. Rock is a rock hound, and hence the very cool design on their personal geocoin. Rock & Crystal started geocaching in January 2003 and as of April 2007 are closing in on 6,000 finds. What is really impressive is their "states cached" map on their profile: I don't think I've seen another map that close to being filled in.
Size: 38 mm | Weight: 33 g