In Minecraft, there are no lives. If you die, you're dead, the only consolation being that in your next life you can backtrack and pick up all the gear off your previous life's corpse. This version of the game, however, does away with even that luxury.
It's called Chain World, the creation of indie game developer Jason Rohrer. It's a Minecraft world that lives not on a server but on a USB stick, and includes a special script that makes the game a decidedly temporary affair.
When you load it up, it plays like any other game of Minecraft. The trick here comes when you inevitably die. Whether you're killed by a monster or just fall to your death, the script wipes the save game from your PC but maintains the changes you made to that world on the USB stick.
You then pass the USB stick onto someone else, who is starting up a life in a world that's been moulded and shaped by the people who have played it before them. Chain World even comes with its own set of commandments governing its use:
1. Run Chain World via one of the included "run_ChainWorld" launchers.
2. Start a single-player game and pick "Chain World".
3. Play until you die exactly once.
3a. Erecting wooden signs with text is forbidden
3b. Suicide is permissible.
4. Immediately after dying and respawning, quit to the menu.
5. Allow the world to save.
6. Exit the game and wait for your launcher to automatically copy Chain World back to the USB stick.
7. Pass the USB stick to someone else who expresses interest.
8. Never discuss what you saw or did in Chain World with anyone.
9. Never play again.
Course, there's nothing forcing a player to follow them; since only one person has the game at any one time, they could make their own rules, only for the next person after that to ignore the both of them.
There's all kinds of other musings and intrigue surrounding the fate of this game, from "celebrity" involvement to eBay auctions, which you can read at Rock, Paper, Shotgun.
The Cult of Minecraft: Chain World [Rock, Paper, Shotgun]