Actually, that one has been proven to be a timed-based kill. The game counts time while your character is not moving. After something like 17 minutes of total inactivity throughout the game, it kills you off. Someone surpassed 1m recently & the footage is on one of the broadcast sites (ustream.tv). Don't stop moving!
[Edit:]
Linkage: debug here - about half way down, posted by Rev John. Link further into the thread for the mill+ attempt by Zimmzamm.