Couple Minecraft with the Oculus Rift headset and the Omni, that virtual reality treadmill that allows you to walk around naturally in a game, and you're bound to get one of the most immerse experiences (currently) possible in video games. You can see what playing with that sort of setup would be like in this video by Virtuix Omni -- which it demos in multiplayer, no less.
What do you think, would you play Minecraft like this? Seems like a good way to lose weight at least.
Virtuix Omni - Minecraft Multiplayer [Virtuix Omni]