At least someone is serious about building starships. DARPA's commissioned a study to find out what advances need to be made before we can feasibly build a starship. No word on how they're doing since starting in October of last year.
Hey, at least it's not some nameless think tank, right?
[fyi: it's a pdf]
http://www.darpa.mil/news/2010/StarshipNewsRelease.pdf