Think Cyberzombies http://www.unseen64.net/2010/01/17/heroes-of-might-and-magic-3-armaggedo... http://www.google.com/imgres?q=%22Cyberzombie%22&um=1&hl=en&biw=1680&bih...

I had a human botnet causing a "zombie" outbreak as it defended itself. Might work well on a small isolated ship. Of course, the whole thing might not be real. Maybe the ship AI decided that since it is Halloween ("Ship, it is June!" "In *your* calendar, yes. I am running on slightly older hardware...") it is time to "entertain" the crew and passengers with a bit of horror. So get some confederates, muses and bots to play the right roles, fab up useful props (everything from zombie skin to nanoswarms) and then begin to manipulate people's AR overlays. The scary thing will be not just the horror play, but that it implies that the AI is either utterly insensitive or creepily mad... "Oh, *I* could never implement a proper scare-the-pants-of-you trick, so I found an old horrorcore subsystem I activated and let run things. It told me it was programmed to keep things safe, and I trusted it. Maybe that was wrong. Cake and grief counselling, anyone?" A piece of sneaky AI software from somewhere that shows an extra, very strange passenger in the surveillance net - at first it looks like a stowaway, then more like a ghost. When the PCs figure out that it is likely just a software glitch or a hack, then have some evidence show up that the ghost actually did something physical. Maybe it was just a commandeered bot, maybe there *is* something onboard. If there are other passengers they might be up to creepy things. The XP abuser who has played so much snuff XP that he now thinks he is in hell and if he just does the right ritual atrocities the higher demons will reward him with demonic powers. The normal guy who was infected with a bioweapon that turns his internal organs into lizards, wanting to break out (or maybe a neuroagent that makes him think that). The petal user who seems to go mad but is actually just experincing his petals... that subtly directs his actions in bad ways, like putting petals in the food fabber - the Lord of Flowers commands it. The former military who did bad things during the Fall and now are suffering flashbacks, haunted by all the people who died because of her actions. The priest with a very dark secret. The reformed serial killer. The scientist on the run from the Factors. The extropian witch-doctor. The person who annoyed Nine Lives and was implanted with a meme virus that will drive him horrifically mad. The muse that refuses to go off-line just because its owner died, and now seeks revenge. And then there is creepy backstory. Maybe the ship was used as a refugee transport during the Fall, and something went bloodily, horribly wrong. This might be combined with the ghost in the net story if you steal from Stanislaw Lem's ghost story Terminus (in Tales of Pirx the Pilot) - that story cries out to be used! Another possibility is that there was an outbreak of the Watts-McLeod virus onboard: everybody became async at the same time, going collectively mad - or there are just these weird statistical coincidences that people who spend a lot of time around the ship end up in bad ways. Maybe there are creepy "psychic echoes" or live viruses around.