Lockette

Lockette is a plugin designed for locking various containers including chests, furnaces, doors, brewing stands, dispensers, diamond blocks, emerald blocks, trapdoors, hoppers, and more.

The Basics
Lockette uses signs. It is the superior locking system because it works especially well with towny servers like LockedCraft. With it, you can also easily see who is added to the container and who is not.