9. Dragon Ball Z: Legacy of Goku 2 - Quick Level Ups
This one is a little more obscure but for those of you who've played Legacy of Goku 2 you might know what i'm on about here. In the game you can play as a few characters from the Dragon Ball series, Gohan, Piccolo, Vegeta, Trunks and Goku. Each have their own barriers in the game which only they can break through, and only at a certain level. At one point in the game you come to a barrier which Goku, the final character you unlock, can break through but you don't have him yet. On the other side of this barrier are some tough dinosaur enemies who aggro to you even though they can't see you. By repeatedly punching the barrier you can hit the enemies without worrying about being hit yourself, although it does activate the barrier and it tells you that only Goku can punch through this barrier. You can then leave the screen and come back, where the enemies will have respawned, so you might do it all over again. Doing this will allow each character to level up to at least level 30 incredibly quickly and allow a good portion of the game to be fought through with ease. Not much of a complicated exploit but one I found as a teenager while playing one day and thought I'd remind everyone of it.
