Wow! There went a couple of hours.
StumbleUpon seems to be a random sampling of stuff that other people found interesting. And, if in not too discriminating a mood, you'll find it interesting too. It is not unlike wandering into a library and picking up books off the shelving carts. Random but fun and sometimes informative. I found myself reading "Calvin and Hobbes" comic strips. I also learned that there might be a
habitable planet orbiting Alpha Centauri. Maybe Spaceman Spiff can go there.

And then I saw a photo of a solar eclipse from space. Whoooaaa! What a fun time vacuum.
I looked at a few other sites, too. Some widget sites, some mobile technology, but several required setting up an account which was just one too many steps for me.
Ning looks like a nice forum for a virtual book club. Hmmm.... Is there a benefit to virtual over face-to-face? I will need to ponder that one.
And my score on the Travel IQ was 93... below average? I need to brush up on my African geography.