In Lost Planet 2 for the Xbox 360, there are shirts you can unlock using passwords on the slot machine in character customization.
From any character customization screen, press Y to bring up the slot machine, then X to bring up the password entry screen and enter the following:
4Gamer.net Shirt – 25060016
Black Shirt – 6315256
Blue Shirt – 56428338
Famitsu Weekly Mag. Shirt – 73154986
Famitsu.com Shirt – 8802023
Midnight Live 360 Shirt – 69088873
Pink Playboy Shirt – 34297758
Purple & Tan Shirt – 65162980
Street Jack Shirt – 12887439
Xbox 360 Shirt – 94372143
Yellow Shirt – 96725729