A friend told me to clean the finger contacs of a DIMM memory module with an eraser :))).. I told him don't do it that way because you will get esd damage.... am I wrong????
To be honest, I don't know the answer to this. I think the main thing is that you should wear a wrist strap to ground your body while handling the module. If you are not doing this the risk is far greater that ESD from your body will damage the module.
If you are wearing a grounded wrist strap while handling the board, and working on a grounded work surface (if you are using a work surface), then I think the ESD risk from static generation as you rub the contacts is probably small.
There must be a better way to clean the contacts, but I don't know it.