http://www.madsci.org/
A free, web-based Ask-A-Scientist service. Anyone may submit a question to be answered by people actively engaged in science education and research. Its online archives contain thousands of questions and answers.

http://www.hotornot.com
Remember the rate-how-hot-my-picture-is phenomenon that actually inspired a TV show? Well, hotornot.com is still around and, judging by the continued influx of pictures and the frequency with which users check their ratings, it's still extremely busy. It contains over 25 million user-submitted photos.

http://www.ultimatearcade.com/
If you have the kind of job where you can get away with playing Pac-Man without raising eyebrows, well, more power to you. You'll definitely want to take a spin at UltimateArcade, which recreates '80s classics in Java and Flash, and offers copious arcade interpretations of its own as well.