The Deepsouthwest Geocaching Project ( http://www.deepsouthwest.com/ ) has been around a while, but I just learned of it from the Terracaching.com forums.
The novelty of the DGP is its ChallengePoints system. It's a scoring system based on the find rate of a cache. The theory is that the frequency that a cache is found is an indication of the difficulty in finding it. From the Web site:
"With the ChallengePoint scoring method, each cache is given 100 points per year it exists. A 6-month-old cache would have 50 available ChallengePoints, a 3 ¼ -year-old cache would have 325, etc. All cachers who have found the cache get an equal share of the available ChallengePoints for that cache. For example, consider a 1-year-old cache, worth 100 ChallengePoints. Assume 20 cachers have found the cache. They each share the available 100 ChallengePoints equally and the cache would be worth 5 ChallengePoints to each finder. If 50 cachers had found the cache, it would be worth 2 ChallengePoints to each finder. If the cache had only been found once, that cacher gets all 100 ChallengePoints."