Oct282011.com
This website had messages and puzzles that no average person could figure out. It also had a countdown clock that people suspected led to the armageddon. Once the site reached the date in the countdown, a mysterious phone number appeared, and if you called it, you heard a weird noise.
Soon after, the site mysteriously got wiped from the web, and most believe it was a secret test for the CIA, NSA or the Illuminati to recruit new members.