If you're a fan of widgets, neat little applets that live on your desktop or sidebar, you'll most likely be a fan of Yahoo Widget Engine. This freebie from Yahoo lets you choose from hundreds of great mini-applications that do just about anything you can imagine--and probably plenty of things you can't. When you download it, you get the engine itself plus a starter pack of widgets that includes a clock, a battery monitor, a stock tracker, an e-mail checker, a weather widget, and others. You can position the widgets on the side of your screen or anywhere on your desktop.

Yahoo's site has plenty of other free widgets, including RSS readers, games, an iTunes remote controller, and even a tuner for listening to Sirius satellite radio on your PC (but you'll need a subscription for that). You can even find a widget based on the TV show Lost, in which you can enter the numbers "4 8 15 16 23 42" every 108 minutes, just as the characters did down in the hatch.

| Price: Free