A coworker recently told me he finds some really cool stuff using Stumbleupon. Now, I had heard of Stumbleupon before, but I had never tried it. I'm not sure why. The concept is cool.
I gave it a spin today, and here's my experience so far. Account sign up? Fairly easy, though it did kind of nag me to use a facebook account and import some friends or something. Once that was setup, it was fairly straightforward.
So far I've found a couple of really cool links, after telling it I liked ~35 things, and disliked 5, and skipping a few.