Two KSP mentions:
Q: In order to use the full MCT design (100 passengers), will BFR be one core or 3 cores?
EM: At first, I was thinking we would just scale up Falcon Heavy, but it looks like it probably makes more sense just to have a single monster boost stage.
Q: Nice to see you are doing things the Kerbal way.
EM: Kerbal is awesome!
The second one:
Q: "Hi Elon! Huge fan of yours. Have you heard of/played Kerbal Space Program? Also do you see SpaceX working with Squad (the people behind KSP) to integrate SpaceX parts into KSP?"
Reply (not from EM): What do you think SpaceX uses for testing software?
EM to Reply: Kerbal Space Program!
Short version - Elon Musk likes and plays Kerbal Space Program.
