Konfabulator would be great IF it were free, and not just a free trial. The OSX version is unrivaled. Nevertheless, there are some great widgets for Konfabulator and its style fits my preferences better than other proograms. However, if I remember correctly it's a little memory intensive on the Windows version. Unless they've made some changes, each widget takes up a small chunk of memory, but it's not a large problem unless you use quite a few at once. You can check this by opening up your task manager and taking a peek.
I don't mean to thread hijack, but try <a href="http://www.kapsules.shellscape.org/">Kapsules</a>. It's free and <i>almost</i> as cool as Konfabulator.
Seems they're updating the webpage and the program right now, so you might have to wait a few days on that one.