there's a cheat/glitch in the first Ratchet and Clank game where you can glitch up one of the races so your onfoot and positioning yourself under a bunch of creates so they're off screen and using a soundwave weapon (can not remember it's name), thank to how the creates re-spawn during the race you can build up the bolts to by the Rhino and turn all your weapons to gold ones.
the drawback is that if you do it for too long you can "burn" this ring into the disk which can make the game unstable or even unreadble
given that, what's the likely hood of something similar to happen in today's games, the glitch in Ratchet and Clank was fixed up in PAL copies and the HD Re-release would have that fix but i'm more thinking in terms of something like these examples
in an RPG, being back and forwards in a small location to get random encounters to grind exp, even going so far as to have a controller or macro repeatedly press the confirm button so just the basic move is performed
Having the game in a pause screen or menu where the game is effectively paused