One of these guys: http://www.apple.com/magicmouse/
Wireless mouse for your Mac, does cool stuff.

It's basically new, I used it for about a week when I first got it but that's it. I can't play starcraft well with this thing so I really don't want it. It cost me $69, I think $50 is about as cheap as you could probably find this online, plus I won't charge shipping and handling or sales tax! It's still in the little plastic box with instructions and everything, batteries included.

Let me know if you want it!