Konami Code in Bioshock Infinite
Irrational Games announced back in January 2012 that Bioshock Infinite would have a hardcore 1999 Mode. It turns out that this mode can be enabled with the Konami Code in addition to beating the game for the first time.
At the main menu:
Xbox 360 / PC: Up, Up, Down, Down, Left, Right, Left, Right, B, A
PlayStation 3: Up, Up, Down, Down, Left, Right, Left, Right, O, X