If you're tired of Windows standard gray clock, use Chameleon Clock and spice it up!
This easy app enables you to customize Windows clock by applying a dozen different skins, besides improving its basic functions and adding some new ones.
I personally found some skins to be a bit excessive, especially in terms of the space they take in the taskbar. This means that if you want to keep the clock within reasonable limits, you probably have to tell Chameleon Clock not to display date.
As for the extra functionality, it turns Windows standard clock into a really useful tool: not only does it tell you the date and time, but can also handle your pending tasks and quick notes in a full featured calendar you can see just by hovering your mouse over the clock.
What's more, you can schedule quick reminders and alarms, use it as a stopwatch and also make sure your PC is on time thanks to its direct connection to several atomic time servers on the Web.
Chameleon Clock brings Windows clock to life with new handy functions and a handful of skins, although some of them are a bit tacky and take way too much space.