Jeff Russell’s STARSHIP DIMENSIONS is a great sci-fi resource for GMs, as well as an all-around fun site to visit. It lets you compare famous sci-fi spaceships — everything from Cardassian Keldons to Imperial Star Destroyers — side by side and in scale with one another.

If you use Internet Explorer (hissss!), you can even drag the ships around on the page for more direct comparisons (which rocks on toast).