Travel across the world
Every now and then you can count on Google to come up with a solid time-waster. This is one of them. It's called Smarty Pins, and it'll have you dropping your Google Maps marker all over the world in the name of trivia.
The idea behind Smarty Pins is to simple. The game asks a trivia question, and you drop the marker wherever you think the answer is. It subtracts the number of miles that you were off from the 1,000 you're allotted at the beginning. Once those are gone, it's game over, man.
Smarty Pins gets a little odd when it wants a very precise location, requiring a lot of zooming in and moving around. However, if that's the case, you probably won't lose more than a few miles if you were looking in the right place, anyway. Besides, if you lose, that just means you get to start over again, and take a new crack at your personal best.
Smarty Pins [Google Maps]