Never mind the constraints of the miserable present: the shrinking budgets, the lost opportunities, the collapsing morale. Thinking is free, so let's think really big. Let's think about ... building a starship in the year 2112.

Well, I've already been thinking about that for decades, actually, but that was just wishful thinking. Now there's a whole organization for thinking about it, with a proper budget and government support and participation by private enterprise, and last week they held a public conference in Houston, Texas: the first annual symposium of the 100 Year Starship Initiative.

The sessions had ambitious titles: "Time and Distance Solutions"; "The Mission: Human, Robotic or Reconstituted?"; "Destinations and Habitats"; "Becoming an Interstellar Civilization". But the organizers also realized that this project will take as long as building a Gothic cathedral: One session was simply called "Research Priorities for the First Ten of 100 Years". Then they'll have to set priorities for the next 10 years, and the next, and the next. ...