Something Is Awful (Website/Hoax, Richard Kyanka/Dr. David Thorpe/Kevin Pereira/Chris Putnam, 2005)

When a writer for notorious comedy website Something Awful got a TV interview on G4's Attack of the Show, the website's owner instructed him to prevent people joining the site as a result by making it seem terrible... and to give the wrong URL, which led to a phony site, which you can view on the Wayback Machine here.

You can watch the interview here, and read a little about its history in a contemporary NeoGAF forum thread here.

You can learn a LOT more about Something Awful from the podcast I'm From the Internet.