OK, so this one isn't just for Lasers. (This joke works better if you say it, not write it.) Three ropes go into a bar for a drink. The bartender says, "We don't serve your kind here." They leave, but one of them is really thirsting. He ties himself up and rolls around in the dirt for a while. He goes back inside and sits at the bar. The bartender says, "Weren't you just in here?" The rope says, "'Fraid not."