My money's on 69.

Rudy Rucker had some interesting conversations with Gödel about a deterministic universe in which (because time is illusory) backward time travel exists: http://www.rudyrucker.com/blog/2012/08/01/memories-of-kurt-g...

Thankyou - fascinating account.

I particularly like how, in describing Gödel's office, he mentions "On the empty desk sat an empty glass of milk." The paradox seems appropriate.