Yahoo! recently bought out a product called "Konfabulator" which happens to be a cool utility for both Mac and Windows pc. The product previously required a registration fee to use past the trial, but now it is completely free!
Check this out for yourself. Here is a tip I posted on HintsAndTips a while back and just updated that explains a bit more about it:
http://www.hintsandtips.com/ShowPost/258/hat.aspx
If you prefer, you can go directly to the site to download the product at:
http://www.konfabulator.com