Sometimes ROM hacks don't need to revolutionise the world or reinvent the wheel. Sometimes, they just need to give you access to tonnes of hammers to make defeating enemies from afar much easier.
Smplhax has come up with a ROM hack of Super Mario Bros 3 that brings more Hammer Mario power-ups to the game, making them more common when pushing blocks and giving you some iron-age firepower when attacking Bowser's minions.

According to the official ROM hacking page, the patch comes in 'two flavors, one normal and another one where any suit Mario reverts to small when taking a hit, to balance out how powerful the hammer suit is.' I'd like to see them try to take this power-up away from me (more than the 3 times it's already happened while writing this article).
If you're in the market for trying out ROM hacks, don't forget to check out our list of the 10 best Super Mario World hacks while you're here!