From Bruce Schneier’s Crypto-Gram of 15 August 2003:
It’s actually easy to fly on someone else’s ticket. Here’s how: First, have an upstanding citizen buy an e-ticket. (This also works if you steal someone’s identity or credit card.) Second, on the morning of the flight print the boarding pass at home. (Most airlines now offer this convenient feature.) Third, change the name on the e-ticket boarding pass you print out at home to your own. (You can do this with any half-way decent graphics software package.) Fourth, go to the airport, go through security, and get on the airplane.
You can even make a knife on board the plane. Buy some steel epoxy glue at a local hardware store. It comes in two tubes: a base with steel dust and a hardener. Make a knifelike mold by folding a piece of cardboard in half. Then mix equal parts from each tube and form into a knife shape, using a metal fork from your first-class dinner service (or a metal spoon you carry aboard) for the handle. Fifteen minutes later you’ve got a reasonably sharp, very pointy, black steel knife.