You mean like Pelican's G-Grips? (Score 1)

Pelican http://www.pelicanperformance.com/ used to sell a product called G-Grips for PS2 controllers. They were small rubber pieces that you attached to the end of the controller for better grip, and they worked pretty well. Unfortunately, I don't think they make them anymore. I bought a few pairs after I found out about them, and I will say that they are a bargain for $10.