In Oolite, a ship can be considered "über" if it is greatly superior to the core ships in the game. Commonly, "überships" are fast, well armed, and iron-assed. However, if a ship that would be far superior to a core ship was in a universe with ships that dwarf its power, the fact that the ship is "über" is disputable.
The more recent but related term über-weapon has similar connotations.
This is a list of some well-known überships.
Take a look here: New lasers