To activate Force Mode: During gameplay, press ALT-V. Then type LETGO. Press ESC to return to the game.
While in Force Mode:
+/- Decrease damage/Increase damage
ALT-E = Extra life
ALT-L = Unlimited lives

To activate Yoda Mode: While in Force Mode, press ALT-V. Then type ISNOTRY.
While in Yoda Mode:
ALT-J = Level skip
ALT-P = Computer plays
ALT-M = View the cut-scenes

To activate Dark Side Mode: Whil in Yoda Mode, press ALT-V. Then type JOINME.
While in Dark Side Mode:
ALT-S = Super Pilot (Has passed all of the levels)
ALT-D = Debug mode toggle
ALT-C = Capture screen shot