Heres an idea I had today which I am implementing for ShadyAcre village.
Apparently, in bottleneck they are building a wall of unlit fires, three deep no less, to keep out griefers and such. The idea being that these objects cannot be moved, but only slowly burnt down.
Building on this idea, I am setting up a log cabin to be a designated 'vault' for holding the most valuable items we have, such as steel bars, coins, etc. What I am going to do is set up a wall of unlit fires around it, with a narrow path to the door that can be quickly filled in. Now, if this is, say, three thick, then that is nearly three hours? of waiting for a potential thief to make before they are able to access what is inside. And really, you could make it as big a gap as you wanted, although at some point it is going to be a major hindrance for yourself also. The point is that this may give us a better chance of catching/interrupting said thief, is discouraging them from even trying in the first place.
This is not idea for objects that you might actually want to use at short notice! As you too would have to wait for the same length of time to 'unlock' the vault. However, if you have more valuable objects such as steel bars/coins than you can reasonably carry around your person, I think this is a good solution.
For an even more uber, upgraded version... consider this.... I know I am!
Instead of a log cabin, surround an area three or four thick with unlit fires. In the middle, set up a grid of baskets/chests/etc. I am talking, twenty by twenty even. A really big grid. Then, you store the valuables in just one of the chests. Then you can alternate which of the chests it is stored in each day or whenever, and share this information among those you trust. So, not only does the thief have to wait ages to burn their way into the vault, but they ALSO have to hunt through a hundred or however many containers to find the one containing the valuables. It basically makes it far too much bother!