I was hoping to play a ship's AI in a sci-fi world.  I had two ideas for plots, though I'd like to come up with a final plot along with my co-gm, who would hopefully play as my Captain.  My two ideas were:

1) Andromeda RP where we are fighting off the Nietzchean invasion in the war that caused the Commonwealth to fail.
2) I am an Alien ship that was sent to Earth to recruit people to fight off a conquering race.  The United Protectorate watches over primitive worlds so that people can't interfere with them too much, and, from time to time, recruits people from the primitive planets under its control. If they can make it to one of the UP base worlds with the ship, they will be accepted into the formal training for crew, and be able to keep the ship to defend their world.  Last time this was tried (150 years ago) the crew died because of mutiny and explosive decompression, and the ship was reassigned to a different race.