"But I don't play MMO games," you say. "You shouldn't be playing games at school," your parents say. It doesn't matter. Whatever you're using your computer for, a good mouse makes your life better -- that's all there is to it.
The Naga ($79.99) has a 5600dpi laser sensor, 100Hz "ultrapolling" with a 1ms response time, and up to 200 inches-per-second tracking, which all just translates to speed and precision no matter the task. The 17 thumb buttons, while great for games, can also be programmed for shortcuts and macros in "regular" applications.
The Windows- and Mac-compatible mouse even comes with three side panels to customize it to your hand size. There's also a wireless version, the Naga Epic, for $50 more.