I've always enjoyed riddles and, with Sleepers PIF, I figured there should be a riddle thread. It'll run similar to the other guessing threads out here. I'll start with a riddle and then once someone guesses the answer and it's confirmed then they will post a riddle. So here goes:
What is black when you buy it, red when you use it, and gray when you throw it away?
What is black when you buy it, red when you use it, and gray when you throw it away?