THAT'S NOT AN URBAN LEGEND! MY FRIEND TOLD ME HE GOT IT, SO IT MUST BE TRUE!
So then what's #1 for urban legends? I've been told that Mortal Kombat has a character named Hornbuckle, there are moves called Fergalities, and I'm sure there are more.
Others:
Final Fantasy II: Rydia can learn Big Bang, Kain is also Cecil and Golbez's brother, and some assorted stuff about secret weapons that require doing really dumb time-consuming things to unlock.
Final Fantasy III: Gogo is Darryl, or Golbez, or Cecil, or General Leo, or Ziegfried, and CAN BE REVEALED AS SUCH.
Final Fantasy 7: If you beat Seraph Sephiroth with the Buster Sword, you can unlock Zack.
Pokemon Red and Blue: Missingno is "Pikablu" and Mew can be found by using Strength on a truck. Mew will be under there.
Sonic Adventure: Press L, R, A, B, X , Y and Start to get Metal Sonic. (You know what that does...)