Kensington Expert Mouse rulez! The ball that comes with it is exactly the same size as a standard cue ball! Sitting next to my black and grey NEC keyboard it looks so cool with the 8 ball sitting in it and it is very precise. Plus, the software is extrememly customizable and the cursor leaps to the deault prompt on every page, both left buttons are "click", top right is "right click", bottom right is "double click" and both bottom buttons together are "scroll".