I bought a GameShark for my PSX and N64, but I rarely used either of them. Most of the time I would just put in glitch codes, but occasionally, when I would purchase a game that was much harder than I had been anticipating (i.e. Shadowman), I would pack on the infinite health codes. I don't like using the GS any more than that because I've had one too many files corrupted by shitty codes.