Here's a tip: You're supposed to open your ball mouse up and get all the stuff that's accumulated on the rollers off, it's a load of general detritus, and probably mostly yours. If it's in a school or college, god forbid, a mixture of everyone's wrist grease and general dirt. Once you've cleared all that crap off, use a can of compressed air to blow any fluff out of the rest of the case. The ball should stop binding then, takes a couple of minutes, simple maintainance.
