How can I polish my frets? I've noticed that the higher frets on my Strat aren't nearly as shiny and clean looking as the lower ones. I got to thinking that's probably killing my sustain a bit (not as much metal-to-metal contact), which helps explain why I don't like playing up there so much (particularly while bending). Any tips on cleaning those suckers up? The most I ever do is a good wipedown with just a cloth after removing old strings and before putting on the new ones. I think I've heard something about lemon oil?... Just in case it makes any difference, the Strat has a rosewood fretboard.