At one of the best Halloween parties I've ever attended, my brother's friend showed up in a clear plastic rain slicker. He had random pieces of tin foil taped to the slicker. For the life of me, I couldn't figure out what exactly he was supposed to be; there didn't appear to be any rhyme or reason to how he had taped the tin foil. He told me that he was the Tin Man. It was awesome; I totally didn't get that. I thought that maybe he was dressed up as a homeless dude trying to insulate himself.
At the same party, my brother dressed up as the son of a preacher man (oh, how true!) but he was a preacher, too. He was a bit too into the costume because he kept blessing everyone.