I have a Microsoft Wireless 2000 keyboard/mouse combo, and while I like it a lot, I find that the rubberized coating on the mouse tends to wear away and/or get sticky feeling within a few months of heavy use.
I initially tried using Armor-All on it, and that helped a bit but not for long. So after reading about the issue elsewhere, I decided to remove the coating and just get down to the plain smooth plastic.
I used a Magic Eraser, lightly dampened at the corner with some 91% isopropyl alcohol I keep around for electronics cleaning. I had initially tried just a paper towel, but it was slow going; the Magic Eraser really moved things along.
Note: rubbing alcohol, especially in the stronger percentages, can harm wood finishes and other surfaces. I did all of my work on a dark hand towel folded so there were 4 layers of it between my work and the table.
Melamine foam, which is what Magic Erasers and other similar items are made of, is pretty cool stuff, and is deceptively spongy, but shouldn't be used on skin or other sensitive surfaces.