Konfabulator

Yahoo! recently acquired Konfabulator, a nifty little program that
allows you to do anything with your desktop. Konfabulator is a base
programs which runs a number of smaller programs (called widgets)
right on your desktop. There are calenders, clocks, calculators,
notepads, music players, games and program launchers to replace icons.
If you have net connectivity, the possibilities are endless, blogging
clients, newsreaders, webcams, and forums all end up right on your
desktop. All these programs are, by design, highly configurable, and
you can fine tune them for your needs.
Konfabulator gives your desktop a major facelift, and all the widgets
blend seamlessly with any background, as fading and transparencies are
used for the XP OS. Konfabulator is cross platform and is available
even for Mac systems (was infact, originally designed for it). The
best thing about Konfabulator is that if you know a little scripting,
you can make your own widgets. You can program a widget to cycle
family photos on your desktop, keep track of the updates in your
favorite websites, and even one to show your current PNR status if you
are travel a lot. Konfabulator is based on JavaScript, which ensures
that you can convert your desktop to anything you want it to be.
Konfabulator can be downloaded from http://www.konfabulator.com/download