I got a Logitech optical scrolling mouse to use with my laptop when I have it semi-permanantly set up in my dorm room, well worth the money. After using my old mouse (which has to have an out-of-round ball or something) the optical mouse is simply wonderful. So far, the optical mouse also seems to have a much greater time between cleanings. My last mouse needed cleaning about every 1-3 months (&^%$ cats get their hai everywhere). I think optical mice are kind of like scrolling mice and power windows, if you never use one, you can get along without it, once you try it though, there's no going back.
Zenmervolt