Another vote for the logitech - comfy enough to play COD4 for hours, with enough precision, and also to use for work. Loads of butons but they don't get in the way if you just want left and right click. Mousewheel works up and down and left and right. And the laser is almost under the tip of your thumb, so fingertip usage is excellent!
_________________________
Rory
MkIIa, blue lit buttons, memory upgrade, 1Tb in Subaru Forester STi
MkII, 240Gb in Mark Lord dock
MkII, 80Gb SSD in dock