Stacking
Use this to open doors when you don't know what may be lurking behind them. Make sure you pick the lock or use a key on the door first if you have to. Lay one guy down, and move him right up to the door. Put another guy in the kneeling position, and move him behind the guy laying down. Stand a guy up and move him behind the guy kneeling down. Now you have three guys ready to fire through the doorway once you open it. Put everybody on "agressive" mode, your guns on burst, and use the guy laying down to open the door. anything in the immediate line of sight turns into a bloody mess. Raider bosses die quick this way.

Unlimited Action Points in demo version
Get down to 1 Action Point in turn-based mode. Quicksave and then quickload the game. All Action Points will be restored for that certain character.