My friend once had an Action Replay. It got me cheats for Pokemon Ruby, a.k.a. unlimited Rare Candies. Took all the fun out of the game, since all my Pokemon were level 100 and I was only on the 6th gym leader. I believe it also gave me Jirachi.
As you may be able to tell, this was a while ago. But yeah, I prefer to play the game legitimately.
i had a gameshark dunno if they count as the same i had 2 different versions on ps2 never really used them to cheat mostly used them for gta 3 and vice city to have fun with i miss those things
I have one and use it after I beat the game, like when I was ten I used it to get lv 100 pkmn after I finish the story do when I play my friends I pown them Or I use it when I get stuck on a level to beat it then continue
On the topic of using codes for gaming, I would use codes after I beat the game. Now, there may be a rare sliver of events which I would use codes, but only if I am in an area of the game which requires me to pass based solely on luck. Castlevania: Portrait of Ruin, I'm looking at you. I'm talking about the time where you must chant a spell for a good 20-30 seconds, standing still, while your buddy fends off two main bosses that frequently use AoE spells. To me, requirements to pass like this really shouldn't be applicable in a game, unless it's a game within a game (gambling games which use luck, like in the Fable series). So I just used a code to instantly cast the spell and I was on my merry way.
The Action Replay was a pretty good tool, except it was limited to the games you currently have. It had a broad library and all, but if you use codes excessively, some games may not be up-to-date and have little to no codes. I instead have a cartridge that comes with both games and complete codes, but uhh, this isn't a particular site to discuss hardware like that :S