Clock Tray Skins is the advanced replacement for standard Windows tray clock. See the time, seconds, day, date and system UpTime in different skins. Displays the time for any of the time zones. Over 100 skins are included in the distribution. Support Longhorn clock style. It's also an atomic-time synchronizer and Calendar. Version 3.7 may include unspecified updates, enhancements, or bug fixes.
Editor's review of Clock Tray Skins Is your dull system-tray clock getting you down? Clock Tray Skins has plenty of inventive styles and colors to dress it up. One displays the time in Japanese characters. Another makes the date and time look as if they've been sketched into your system tray.

Additional features include a basic calendar, random skin selection, and synchronization with an atomic time server. Changing skins is as simple as right-clicking the clock, selecting the main dialog, and choosing from a window of options. Clock Tray Skins isn't a must-have by any means, but it's a simple way to jazz up your desktop.