Players are on a generational spaceship that went off course generations ago and they have lost a great deal of knowledge since things went amok. The ship is a few technological levels more advanced than the players tech level. The players are probably pretty close to modern technology, and the ship is 40-50 years past them.
There are plants growing all over, perhaps broken free from giant "greenhouses". A lot of the ship is just automated on the actual running necessities, but interior maintainence has broken down. There probably aren't much in the way of weapons, makeshift probably.
Campaign Ideas that have occurred to me is to have the ship break down after a few sessions and crash on a habitable planet, heck, or maybe not even really habitable, but that'd be easier. There's not much edible on the planet, and the players would have to live off of plants from their ship, perhaps even planting vegetables and fruits from the ship.
I'm picturing an alien race of comparable tech who would probably want the generation ship's technology. Lots of wild animals, maybe dinosaur-like.
