Chameleon Clock - description from Softdepia.com:
Chameleon Clock is a desktop clock which purpose is to be useful, user-friendly, and beautiful. It is where the power of both features and interface is combined with simplicity. Check how Chameleon Clock makes a standard Windows tray clock a tiny piece of art by using Winamp skins and bitmap digits. Several skins are included in the distribution as examples; and you can download more from our collection or from numerous other places on the Internet.
Chameleon Clock is a "Free to try" program. You can download and try it for an evaluation period.