Video games themselves are also a great source of ideas for builds and, after roaming through Bioshock’s underwater city of Rapture, Minecraft forum user TraktorHagrid decided to build something submarine. It’s all very claustrophobic and very metallic, but certainly true to the spirit of Bioshock. You can find many more images here.
(Naturally, someone else just had to go and remake Rapture itself. Adam "Ein" Shefki hosted a server on which Penny Arcade forum members came together to recreate the city way, way back in 2010, when Minecraft itself was still in alpha.)