Chlorophyte Extractinator

The original machine is a slot pull you feed sludge into one item at a time. This one runs several times quicker, which alone makes bulk processing bearable, but the bigger change is the output table. In Hardmode it starts returning the first tier of Hardmode metals, so a mining trip's worth of junk turns into ore you would otherwise be smashing altars for. Bring one into a pre-Hardmode world and that part switches off.

It also swaps things for their opposite numbers. Ore and bars flip between the two metal types, which is how you get the one your world never rolled without visiting somebody else's. Blocks touched by an evil biome or the Hallow come back as the plain version, useful after a purification pass leaves you with a chest full of the wrong stone. Glowing mosses turn into any color you like, and dungeon bricks shuffle between their styles.

Wire one up and a signal makes it pull from chests sitting right beside it, so a stocked container and a timer will grind through a hoard while you are off doing something else. Set that up once and you never manually click the Extractinator again.