Okay, I’m hooked on the online game Desktop Tower Defense (thanks Jeff and Tony). The basic idea is you start with a certain amount of gold, which you use to buy different towers. You arrange the towers on a map, which are used to kill bad guys trying to cross the screen. If 20 bad guys make it to the other side, you lose. The strategy is in what towers you place where, and how you spend your gold to upgrade their power.

Anyways, it’s pretty addicting (you’ve been warned)…