Ok, I don't really use cheats much these days, as in codes or subverting the programs.
I do occasionally glitch(L4D has rooms where zombies don't attack on the Finale for example), when I see an impossible(for me) or otherwise irritating obstacle. You see, I know approx. one good player, and I don't enjoy trolling the servers for actually players amongst the idiots, so I got my buddy and WE got through expert, using a little aid to stop the damn idiot computers from fucking us up.
Also have used walkthroughs for certain things, usually puzzles, because after an hour of banging my head against the wall with a puzzle, the purpose of my gaming(recreation) is gone, and It is entirely possible I TRIED the right thing and the game is glitched or something.
One time in KoToR, I got on trial on Manaan, I tried every dialog option I could think of, and died every time, only to find out the logical choice(accepting a court lawyer) guaranteed your death. Thats not cool, Basically the only way to not die is snub the lifeline,it made no sense and I almost quit the game because I simply had no idea what to do.
As for farming etc, depends, I have been known to powerlevel, or take a lvl1 borderlands character to a 2nd playthrough Eridian Promontory so I can get him to 40 in ten mins.
But realize how many guns and upgrades I never find doing that, I am trading loot for speed, its a choice.
I have even boosted on occasion, mostly Cod4, I was really good at the competitive mode, but headshots take forever, and I really didn't want to lose my accuracy rating(was over 20 for a bit), and risk my ratio(55000/43000 or similar), to get them, so I did some boosting for my Golds. Anyway, I like my G3 and AK-47, giving them up to get headshots for the freaking M16? No.
Finally, I think games are for fun, challenge is personally my style I did MW2 and GoW2 on the hardest mode no prob. But some times there are in game rewards, like extra costumes, guitars and paint colors, that have no effect on the game other than my enjoyment, at which point I seen no reason to be denied my satisfaction, I will cheat conventionally, code or subversion, but since these days, achieving the item I want is either easy or uncheatable, I have little problem. So yeah, I will use codes to unlock the last songs on GH3 even though I cant play Raining Blood, because I don't see why it matters.