A better, cheaper, and smarter solution is to buy "Mr. Clean's Magic Eraser". I bought one, made the edge a bit damp and scrubbed my MacBook's polycarbonate shell. Don't use it on the LCD panel, but the top part of it is fine. It's very cheap, two of those "magic" erasers set you back a few bucks. And the pack I bought had 2 erasers for like 2 bucks. They're basically a foam block. My MacBook had some stains on the palmrest area that I couldn't get off with soap/water, tissue, etc. This magic eraser thing made it feel brand new.