cleaning an oily trackpad

I try to keep my iBook clean, but i'm an oily person and my trackpad (and my keyboard to a lesser extent) have become quite oily.

Using a cloth dampened with a little water does just about nothing to clean the trackpad. Is there anything else I can use to clean it that will remove the oil?

I found this:

http://www.eurocom.com/support/maintain/clean.cfm

Looks like a mild soap is okay.