I’ve just installed StumbleUpon. In their words:
Join 3,762,664 Stumblers & Discover New Sites
Channel surf the internet with the StumbleUpon toolbar to find great websites, videos, photos and more based on your interests. StumbleUpon learns what you like and makes better recommendations.
Connect, Meet and Share
Connect with friends and share your discoveries, meet people that have similar interests, and check out what other people are discovering
I haven’t done any sharing yet, but I’ve had some fun clicking the Stumble button & seeing what it brings to me. A good actvitiy when you have a spare couple of minutes – or need a break from the grind!!