Have you guys seen this yet?
Ben Purdy used projection mapping to create a "real life" Minecraft block. If you don't know what projection mapping is, it works like this:
"There's a piezo element taped to the box and hooked up to an arduino. The arduino senses the physical impact with the piezo element and sends serial data to my PC. Processing picks up the serial signal and takes care of the projection and interaction (particles, etc)." Just hit it with a stick, and particles fall off as you "mine it"— check it out: