I recall reading a short story many, many years ago. One of the major plot elements was that there was a ship powered by some sort of captured god or deity, but I can't recall much more than that? Perhaps something like that they were travelling around the galaxy capturing gods to feed to their own, or something? It's such an obscure idea that I hope that this detail alone might be enough that someone else might be able to point me in the right direction!
Sounds very much like The God Engines by John Scalzi.
From Wikipedia entry:
The story takes place in a universe where space travel is accomplished by chaining intelligent, human-like creatures called gods to a spacecraft and torturing them to drive the ship. The people are ruled by an organization called the Bishopry Militant, who worship a powerful being. Captain Ean Tephe is completely faithful to the Bishopry, but his faith comes under test when he is assigned a secret mission which his ship's god seems to have a keen interest in