So far the biggest improvement anyone's made to a mouse's scrollwheel was to allow it to scroll sideways by rocking it left or right. You can still do this with the MicroGear scrollwheel, but the big thing here is that you can switch it from the normal, "geared" mode - which is the way all other scrollwheels work - to a truly free-wheeling style. With a flick of the finger, the scrollwheel spins freely for up to seven seconds depending on how hard you spin it. The result is much faster page scrolls. To switch modes you have to slide a switch at the bottom of the mouse and this can be a little bit tricky if you don't a suitable prong to hand.



Link: The Reg HArdware