I dont get this. We just purchased on wireless mighty mouse and one wired one came with our imac. We have had them for about 5 months (not long by my standards) and all of a sudden, within days of each other, the little ball scroller broke!! WHAT THE HELL?? One mouse is for my husband's computer and one is for mine, so they are being used differently, not for the same purpose or reason.. However, I'm sure we both use them alot.. but doesnt every one? Is this something thats common in these?? If it is, i will never purchase another one again. I dont care how much BETTER they look than a basic mouse.. I have NEVER broke a mouse..I have one that came with my very first computer around 16 years ago and it still works!