Imagine the tools that we have in the game, but they dont give any materials when used to destroy blocks.
Now to start with this may sounds like a silly idea, but how often have you been mining and not really needed all that extra cobblestone or dirt or whatever block it is, that keeps filling up your inventory.
My idea is to have a tool such as a sledgehammer (hammer) that would break blocks faster (maybe 1.5x) than the other tools presented in minecraft, but it doesnt give you a reward for mining the blocks.
Want to get a long strip mine going without having to deal with the filler materials? Just take a hammer with you. Want to clear an area quickly with friends for your next project? Use hammers.
There are many uses for this and i believe it would be used more than people first comprehend.
It would be crafted by putting 2 sticks and 5 corresponding blocks (wood, stone, iron, gold, diamond) sort of in the shape of a pickaxe, but with the 2 extra blocks put each side of the top stick.
Im not sure if im supposed to suggest enchantments and everything else assosiated with tools, but im not too good with enchanting so i cant provide ideas for that side of things.
Hopefully this idea will take your interest and maybe get the attention of somebody over at Mojang. Be happy to any of your own suggestions on this idea. Cheers