Minecraft is one of the most flexible creation engines this side of LittleBigPlanet, and despite the pretty cool stuff we've seen in the past, nothing comes even remotely close to the synapse-destroying brilliance of the in-game, more-or-less-to-scale Middle-earth created by Shorvok and the hobbits of Minecraft Middle-Earth.
A large majority of the reproduction has been crafted without the use of plug-ins, with incredibly massive cliff-faces and mountain vistas being carved by hand. More than a thousand man-hours have been devoted to the project, and the results are nothing less than breathtaking. If you've got the time, we heartily recommend watching the full video. If you're pressed for time, however, make sure and check out Rivendell at 29:09 and the Mines of Moria at 33:23.
(Please note, neither Joystiq nor Minecraft Middle-Earth can be held responsible for brains exploded in bewilderment.)