Nanaca Crash(click here).Pretty good time waster, I'd say. Kinda like that one penguin game, except a little more complex. The game is in Japanese, so I can't really explain the rules, but it's pretty easy to learn. My highest score is 6339.89m.... try to beat that.
Edit: Oh, I should say one thing... click the left mouse button when"Aerial" turns either red or blue, that will give you an extra boost. And when the word "special" appears on the screen, quickly click the left mouse button.