I have one.. its the result of using the mouse several hours a day. The area below my wrist suffers a lot of friction during the day, making it harder.. maybe as hard as the base of my foot. That area below my wrist is kind of red..or dark orange.. and it has lost the sense of touch.
I know what you mean... perhaps 2 hours per day of using the mouse followed by a hard masturbation session almost nightly... I can definately feel it taking its toll.
As the saying goes: "A wank a day keeps the RSI at bay." Though that's not why I do it, I have a trackball and my wrist rests on the handy wrist-rest.
I've been using a computer (and mouse) for 10 years, and I've not had anything like that. Dogzer, you might be confusing the mouse with a toaster. It's an easy mistake to make, I can tell you.