Then there's the likes of Chain Letter, a teen-scream of the 21st century in which breaking an e-mail chain means certain death for a group of high-school friends. Each e-mail they receive--usually on their cell phones, natch--comes with the warning that if they break the chain, they will lose their life. The sender of the letters, The Chain Man (ugh), isn't kidding around and each teen who treats the letter as a hoax is brutally murdered.
The tagline on this winner is "Every chain has a link, every link is a life. Break the chain, there will be pain. Pass it on." Here's another warning: Unless you're a diehard horror flick fanatic, you might want to just pass.