sugru. Have you heard of it? I don't think is has made it state-side yet (It's a U.K. website), but I sure do want some!
It's made with silicone and looks like a glob of modeling clay. It sticks to anything and you can shape it with your bare hands. If you want to use any kind of tool to shape it, you need to make sure it's covered in soapy water so it won't stick to the Sugru. You don't have to rush too much, as it drys within 30 minutes. And it cures in 24 hours, and then it will not come off, even if you run it through a dishwasher or heat it up in a conventional oven! How cool is that?
Oh the clever things I could make - or customize - if I only had some of this stuff!