"Dean," a Carnegie Mellon freshman who is tired of his dorm-mates getting locked out of their rooms has developed a door-unlocking tool that consists of a length of copper wire that "slides under the door, flips up and grabs hold of the handle on the inside so that you can pull it down" -- inspired by a classic MIT pranker's tool. He details it here.
The best part about using copper wire is that it rolls up easily. You can keep it in your pocket! I also bought some 1/4" wide 20 threads per inch bolts (which fit right into a standard camera tripod hole) while I was at Home Depot. I figured the tool would be more useful, and look less suspicious as a tripod. This shape of bend prevents the bolt from moving when the camera is attached. It is a very strong bend because it wraps perfectly around the head of the bolt. I added a little duct tape to cover the scratches made from my pliers.Link, Backup Link (via Make)