Sometimes I enjoyed the days of platformers in the NES days and before where they were
so difficult I felt like cheating was necessary and fair just to be on an even par with the game.
In PC games God Mode can be extremely fun. For example, in Blood just runnign around and blowing stuff up in a way that you wouldn't even be able to come close to achieving.
In console games, I've never really felt the need to cheat much from the SNES onward. I do intend to play through Silent Hill 3 again now that I have beat it and can get the Uzi with unlimited ammo, though. It's nice to have the option, at least, to go through the game overpowered after you've beaten it once, but on the first time through it does cheapen the experience for me.
Jam it back in, in the dark.