OK so I read through a lot of the posts and thought of this. Oh BTW crash spout works on macs
Ok so you want to lock a chest. You could do /buy ironlock (or something to that effect). Then your character would have one "iron lock" in possession. (You would have a database with all the character names and then a number for each amt. of lock). Now when you wanted to apply that lock you would do /lock iron (or something to the effect). The next chest you opened would have the lock applied. This lock would have 100% durability.
Now for the picking. When you use a stone hoe on it, it would take a low amt. of durability off and would require a "cooldown" (this simulates you actually trying to pick the lock). If you used a iron hoe it would take more durability off per use. Diamond more, and gold more etc.
This would be very cool in my opinion. It would still make giant locks useful because you would want to keep them away from your locks so not as to lower the durability.
Oh and you might want to make it so everyday you don't open the chest the durability goes down, because then if you come to an abandoned town there aren't a ton of hard to open chests, when the locks would have rusted off.
Any comments and suggestions would be appreciated. Now back to working on my computer.