Super Mario Maker (originally named "Mario Maker" to match "Mario Paint") recently released for the Wii U and it got me to thinking. You know those ROM hacks where people add new levels to old games? Surely some of those exist for Super Mario Bros. 1, JP 2, USA 2, 3, and Super Mario World, right? So what are some of the grandest ones of them all, the ones worth downloading and patching into the games?