I got one.

When you're in your high school's computer lab or library with computers on a network do this.

When you're sitting next to somebody on the network that's computer stupid. When they're trying to print something unplug the cable from their NIC card. Then right when they get up to find out why nothing came out of the printer, type up a word document saying the word "OWNED" in large bold text with their name on it and print it as they are at the printer.