Razer Lachesis. Just friggin' awesome. I had intended on buying the Death Adder, but there sat the Lachesis right beside it and... well, yeah.
All the Razer mice are great. They have a different feel that some don't like, but I love. They are "finger" mice, not "wrist" mice. I keep mine cranked up to max sensitivity now that I have gotten used to it. Well, I actually have to dial it down in some games... it moves too fast.