The Toothpaste Fish Citadel lives! Shortly after it went up this morning I fitted it up with missiles and bomb launchers and tried to get it into warp... but so far it refuses to move. I need to watch some tutorials I guess. I suspect it won't fit into anything smaller than a Large Plex, but still, it should be very effective at chasing larger targets.
I also couldn't find any prop mods on the market in Jita. Puzzling.