Suggestions for "slick" mouse buttons?

[BlueWeasel]

I've got a Roccat mouse that is my favorite and is no longer made. The mouse buttons had a slight texture to them but are now smooth and shiny from use. I was thinking of applying small sections of grip tape but there might be something better.

Any suggestions for grip/texture tape or material that can be applied to slicky mouse buttons?

 

[C1]

Fine grit "wet or dry" sand paper.