Key  Effect
-----------
F2 - invulnerable (You couldn't die).
F3 - unlimited_thrust (Your thrust engine is unlimited).
F4 - unlimited_terraform (You could manipulate the terrain all the time).
F5 - unlimited_sparks (You receive unlimited sparks).
F6 - low_graviation (Activates low gravitation).
F7 - no_water (Disables/enables the water).
F8 - no_fog (Disables/enables the fog).
F9 - speed_control (F9 +/-) (You could control the game speed by self)
     (slow-motion-effect possible...).
F10 - win game.