In X-Men: Destiny for the PS3 and Xbox 360, there are some extra costumes for Emma Frost and Juggernaut that you can unlock by entering a code on the Start screen.
Here are the costumes you can unlock, and the buttons you need to press to unlock them.
Emma Frost’s Costumes
Xbox 360: At the Start screen, hold LB and RB, then press Up, Down, Right, Left, B, Y
PS3: At the Start screen, hold L1 and R1, then press Up, Down, Right, Left, Circle, Triangle
Juggernaut’s Costumes
Xbox 360: At the Start screen, hold LB and RB, then press Down, Right, Up, Left, Y, B
PS3: At the Start screen, hold L1 and R1, then press Down, Right, Up, Left, Triangle, Circle