I can not recommend the Logitech MX Revolution enough, it's simply the best mouse I've ever used hands down. The battery lasts so long that I forget to put it on the charger and wonder why it's stopped working... I use this mouse at least 12 - 14 hours a day (min) and it lasts over a week.
It's super smooth, the free spinning scroll wheel itself makes this thing worth it...
http://www.logitech.com/index.cfm/mi...s/130&cl=US,EN
Seriously, I keep recommending this mouse to everyone and every person that gets it absolutely loves it.