"Possibly the biggest feature of this mouse, which I haven't mentioned yet, is the TouchSense Technology from Immersion. This was
introduced sometime last year and I'd thus far not had a chance to try it out. Effectively, it is a type of force feedback technology designed for mice.
Obviously the designers had the constraits of a mouse-sized device, as well as it not being able to force the mouse to move anywhere such as the
case where wheels and joysticks are concerned. So the clever people at Immersion came up with a series of vibrations, which could be modified and
would give the feel of the mouse grating along, or the kick of a rocket launcher in Quake 3."