I am running a game with 11th level characters and like to think outside the box. I asked them about running a side quest to a UFO and they were definitely interested. Since I am an old school gamer and I own Expedition to the Barrier Peaks (AD&D module) from the early 1980's. I don't wish to copy that module but liked the map of that UFO.
My question to you is, as players and GM's/DM's have you ever played through a UFO and what cool things did you have inside? I was worried about technology ruining the game, but I can the weapons/armor run out of energy cells or something like that if things get out of hand. Also, what about monsters, robots, etc...