I've started modeling up a fleet of space opera style spaceships, which I plan to have printed out at some point. I don't have the money to do so at the moment, because I'm out of work, but hey, 3d doesn't cost anything. When printed, they'll range from about 30-70mm in length. I seem to have gravitated towards a sort of Halo/LOGH mashup. Here's the smallest one so far, a standard frigate. The next smallest is the destroyer. I honestly haven't worked out which little surface details are supposed to be escape pods, missiles, or thrusters. They're all sporting them, though, in standard sizes.