Luke Nosek

It is only when you watch the dense mass of thousands of ants, crowded together around the Hill, blackening the ground, that you begin to see the whole beast, and now you observe it thinking, planning, calculating. It is an intelligence, a kind of live computer, with crawling bits for its wits.

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.