I really like this topic:
Arthur C. Clarkes titular
Rama, I love the mystery of the Ramans, their triplicate redundancy and the general science behind the ship.
Peter F. Hamiltons
Oenone in the
Nights Dawn Trilogy (briefly mentioned up thread), these are bitek design, consisting of biology and tech, they are connected to their captains on an intimate level due to the Edenists Affinity gene.
The ships in Kevin J. Andersons Saga of the Seven Suns are interesting:
Wentals, Verdani, Hydros and
Faeros are sort of elemental forces:
Wentals are essentially a water element, their technology is based around exploiting water and using this to great effect.
Verdani are essentially treeships in space, they also have an ability to combine with Wental ships for even more effect.
Faeros essentially use and manipulate heat, with their ships looking like huge fireballs, which fits in nicely with their home in star coronas.
Hydros are probably the most interesting of the elemental ships, they are essentially liquid metal ships that are able to hold pressure through some unknown mechanism, this reflect their nature as gas giant dwellers.
Ildirans have interesting ships, they essentially outright banned AI above a certain level so their ships are complete with Hydraulic controllers and gears/levers.
Klikkis have a sort of modular, hive ship design, where damage can be done to any modules and they just simply reform. They are able to reform into larger and more powerful ships.
Simmons
Hyperion has the interesting
TreeShips which are said to grow in space, captained by Templars who are a sort of Starship Captains guild. Loose on the science but this is Hyperion.
Justice of Toren, from Ann Leckies
Ancillary Justice is a great concept, a sentient ship with human equivalent automatons making up large parts of the crew. Makes for a very interesting sense of consciousness.
I am sure there will be others just as interesting so I will scan my shelves when I get home.