How do I clean the keyboard? Compressed air? What about the metal body? How can I clean the sweat marks by the armrests? What about the slight marks over the speakers? The marks are removable-- but I am worried about using a damp microfiber cloth over it. Finally, how can I clean the little strip of rubber around the glass LCD? A toothpick doesn't help... Here's a picture: http://dl.dropbox.com/u/8494936/17mbp_dust.jpg All these marks are from normal wear and use. In this case, what's the best way to clean the body? I've heard that a white erase marker works... (but wouldn't the shavings get into the speakers?).