Dale, part of the problem is fuel. Maybe you could mention the squirrel-engine idea of mine, where we convert plasma (protons and electrons) into hydrogen by collecting it and then slowing it until it is cool enough that the protons and electrons join up as hydrogen atoms. If a station in Earth-orbit was making fuel from plasma and solar energy, and selling it, spaceships wouldn't need to carry as much fuel up with them. A viable industry might be had from helping others go further!
Back in NY.
The saturday night party was awesome.
Great conference.