That someone was a man by the name of gavers; he used nail polish remover to do the trick. Here is what he said:
"I found that Non-acetone nail polish remover cleans it up nicely. Only problem, my fingers feel like sand paper after using it.
You should use clear, or blue colored Non-acetone nail polish remover. If you use another color it will slightly tint your MacBook that color. Do not use acetone based, or isopropyl alcohol, those may damage the plastic."
Many seem to say that it has worked although it hasn't worked for everyone. ACETONE or isopropyl alcohol based nail polish remover can melt plastic so stay clear of that.
UPDATE: A couple of commenters noted that in the previous paragraph I said non-acetone will melt plastic which contradicts all the previous stuff before it. Thank you to Mark 2000 and Anonymous for pointing that out so I could fix it. The truth is that ACETONE based nail polish remover will melt plastic and not the other way around.
Here are some before and after pics (an old iBook I know but this fix works just fine on Macbooks):