Among one of the more recent maps that was re-released for Trouble in Terrorist town was ttt_shocked. Its a map based off of the System Shock games (more specifically System Shock 2) and even uses models and textures from the original game. It also apparently has a bunch of weird features like an in-game currency to buy ammo and guns (sort of redundant if you're a supporter or higher), secrets, and armories full of weapons and items that can be opened with keycards found throughout the map. Here's a couple of screenshots of the map: The map can be found here on the Steam Workshop.
