get thelogitech MX610.
i bought one and fell in love with it, a day later i went back to the store and bought three more, one for every machine i have. then the other night i found this site http://logigamer.com
download the 'Uberoptions' utility. it allows you to bind anything to any button on the mouse, so your not stuck with limited options. now i love the mouse even more. matter of fact im thinking of hardwiring the dongle on the inside of my machine i like the mouse so much. the only possible way it could be any better is if they came out with a bluetooth laser version, so i wouldnt have to mod anything. theres my two cents, hope its helped.
oh, did i mention this mouse rules?!?!?!