Please understand that I have no intention of disparaging the theme of this thread...I only want to comment that while I love and appreciate the work that many visual artists have created along this line (and which so many of you have reproduced here; my thanks for that!), I have to say that for me, science fiction lives in the images that formed in my head as/after I read words.
And from that point of view, I find that I am generally less intrigued by the shapes of ships as seen from outside, than with their interiors. Thus, I find C.J. Cherryh's Merchanter ships very interesting, and I spend time, every time I read or re-read one of those books, trying to visualize the ship involved. (For that matter, I would say the same thing about the various Stations featured in her books: the image in my head is bigger and better than anything that has made it into anyone's artwork.)
Dave Wixon