95% of all hacks are of games like Pokémon or Super Mario World. If you've even tried hacking something else, put this into your signature.
Megaman 2 (well, Rockman 2) is just as hacked as much as Pokemon and Super Mario World, except that there are less tools (or at least seem to, unless there is a Megaman hacking community out there somewhere), so is EarthBound (though the amount of new EB hacks seems to be dropping by the day)
By the way, were you inspired by my signature to make this one?