Eric Clapton

I remember hearing Sonny Terry and Brownie McGhee, Big Bill Broonzy, Chuck Berry and Bo Diddley and not really knowing anything about the geography or the culture of the music. But for some reason it did something to me - it resonated.

Leave bands, go back to obscurity if I choose to, without a great sense of loss of security because it's all been based on the fact that I did it on my own or was doing, enjoying doing it on my own in the first place.

Supplying fuel for a Mars expedition from the lunar surface is often suggested, but it's hard to make it pay off - Moon bases are expensive, and just buying more rockets to launch fuel from Earth is relatively cheap.