Hive

Hive counts toward Jungle biome requirements, which is more useful than it sounds. A room lined with it registers as Jungle without a single mud or grass block for Corruption or Crimson to creep into. That keeps a Jungle NPC happy or a Jungle fishing spot alive in a world the evil has already eaten, and it is far less work than quarantining the real Jungle.

Breaking a block will sometimes hand you honey instead of the block, and often wakes a bee or two on the way. Clearing a hive by hand means constant interruptions from things you did not see spawn. Take the honey seriously as well: a pool draining down into a fight below is a real hazard, and it will follow you through the tunnel you just dug.

You cannot place Hive by hand, only with a Hive Wand. Using the raw block instead spits out homing bees at no cost and without consuming anything. They count as melee projectiles, so flasks, a Sharpening Station and the Frost armor bonus all apply to them, though your melee damage bonuses do not. It is a novelty rather than a real weapon, but it is free chip damage while you are standing around building.