Ghost Recon 2: Summit Strike

During a mission press start to pause the game, choose In-Game options,
choose Enter Cheats, then enter one or more of the following button
combinations:
B, B, X, Y - Complete Current Mission
B, B, X, B - Team Superman (Team Invinvibility)
B, B, X, X - Refill Ammo
B, B, X, A - Superman (Player Invincibility)

Medals:
Bronze Star                  - Get 15 kills
Congressional Medal Of Honor - Get 30 kills
Distinguished Service Cross  - Get 25 kills
Purple Heart                 - Get wounded or killed in action.
Silver Star                  - Get 20 kills

 