Hi all, I get all sorts of crap on my hands during the day, and I pull out my new touch at random times to do random things, so I don't always have time to give my hands the old scrub down. Is there any types of things I should avoid having on my hands in order to preserve the freshness of the touch screen? I know I should avoid obvious things like paint, gasoline, etc. What else is there? Maybe throw out something that isn't as obvious. Thanks!