Stumble Upon toolbar: The cool web site finder: "StumbleUpon is a completely new way to surf the web. It lets you channel-surf pages which your friends and peers recommend.
Available for Windows, Macintosh & Linux
We are a community-based, word-of-mouth approach to websurfing ; pages you 'stumble upon' come from like-minded people who share your interests. Add the Toolbar, choose some topics and click Stumble! You'll meet people who like your favorite sites as you discover the best of the web.
'I'm hooked on the thing, and rate it as the second most useful web browsing tool after Google itself' - PcPro"