The first is the Federation’s Prometheus class starship, as seen in Voyager and the second is the Romulan Empire’s D’deridex class Warbird, which first appeared in The Next Generation’s first season finale.
The rocket from the 1980’s Flash Gordon movie, because it was so stupidly designed. Why, Dr Zarkov, did you design and build a ship that would kill you if you operated it alone?
The BIG ass ship from the opening scene of Spaceballs. “We Brake For Nobody.” The hero’s Winnebago-ship as well.
Two from Peter Hamilton’s Naked God trilogy. The bitek Edenist habitats (Tranquility and Valisk rule!), and the ships that the race of beings that lived entirely on pieces fabricated from old, derelict ships (from the final book) that used them to fly into their sun to mine it’s energy.
The Puppeteers mobile rosette of five planets locked in formation from Ringworld.