So I used to write a lot of bad sci-fi and came up with the idea a long time ago of taking a Midway [http://www.wcnews.com/newestshots/full/original-midway.jpg] class megacarrier (designed to be a one ship fleet already, fitted with science and marine quarters, anti-Capship weapons as well as anti-fighter weapons and its fighter and bomber compliments) and super-sizing it.
The design I ended up with was bigger than a planet (to give you some idea of size a ringworld [http://en.wikipedia.org/wiki/Ringworld#Ringworld_engineering] is 997,000 miles wide, I came up with a story arc in which one of my ships was modified with creation engines [contained nanobots, able to take a handfull of dust and produce a pistol, or the contents of a solar system and...] to build ringworlds by circling a sun, tug boats and mining ships slicing up and towing the mass to the ship provide the supply.)
I named the flagship the Tuatha De Danaan. The ships were outfitted with various experimental technologies, multiple halo style ship-board AI's and worked as a sort of inter-galactic peace keeping force (later calling themselves 'the order') on behalf of the confederation.
So, yeah, I choose my vast super-midway ship called the Tuatha De Danaan.
