I love those cheapo microsoft USB optical mice, I've had several over the years and have a black one now. Two buttons and a scrollwheel as a third, comfortable and works great. On laptops I prefer the trackpoint but can make do with trackpads. I have a logitech trackball that I like, one that you use your fingers on, I have an ADB thumb one too but I hate it. The only mice I really hate fall into one of three categories: jumpy tracking, too small, or a scroll wheel that doesn't have stops in it (those smooth ones).