The armorstand helper allows you to focus on designing an armorstand's pose, without messing with any code.
This tool was originally written for Minecraft 1.8, but has been updated since then to support all different versions of Minecraft.
A tiny backup utility. It's very fast, saves space by using hardlinks and should be very stable. The binary is less than 4MB!
Sprich (German: speak) is a tool for game developers. It allows you to easily create complex dialogs for NPCs by compiling a simple, human readable text file into JSON you can use in your game.