I can't remember if it was a video or a recent Bombcast but the guys brought up cheats and how you can potentially ruin games with them. This immediately made me think of the original Starcraft. Way back in the day I essentially made that game no fun at all because of the cheats. I still remember some of them, Black Sheep Wall was for getting rid of fog of war and Show Me The Money was 10,000 minerals/gas. There was a tech upgrade and a speed build/upgrade cheat as well but they're escaping me at the moment.
They made the game super fun at first but completely killed any challenge and once the novelty ran out, it kinda sucked. I didn't have the willpower to not use them so the game lost any enjoyment for me and I quit playing. I learned my lesson with that game and have avoided even looking up cheats after that, I didn't bother with Warcraft 3 and now I don't have any inclination to use them really.
How bout you guys? Ever killed the fun of a game with cheats? Or what games did you make better with them?