Clock Tray Skins is a useful program that will extend the standard Windows system tray clock capabilities by adding a day, date and seconds display, as well as a choice of different skins.

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.