Apple Wireless Mouse
Microsoft IntelliMouse Explorer for Bluetooth
Logitech MX 900
RadTech BT500
I own the Apple wireless mouse and it tracks well and gets great battery life, but the one-button and lack of a track wheel drive me nuts. Currently I'm using a Logitech MX 500 that I had lying around. It's wired, but with the right-mouse button, scroll wheel and extra buttons hooked up for Expose and Dashboard - it's much nicer. I've considered selling my Apple wireless mouse and buying the Logitech MX 900.
I use the Microsoft BT mouse on my PC and it works great on the PC, but when I tried it on my Mac Mini, it did not track nearly as well.