This mod places a new vault in the top center of the Fallout: New Vegas map and asks you to survive against killer robots. But rather than sticking you in a single room, you're trapped in a maze. It's a bit like a 3D Pac-Man where you can slam doors shut to block your escape.
The control room from the original Five Nights is recreated in the mod's Vault 5, but the action takes place outside of the control room, in the aforementioned maze. Robots can't see you when you're behind them, so you have to try and stick to their flanks and use walls for cover as you try and survive each night.
To make matters worse, you get irradiated for closing doors (to stop you abusing the mechanic) and a radiation warning pops up periodically - when this happens you have to shut it down before the maze fills with rads, forcing you into sometimes desperate action.
The mod tracks your stats and you can read tips and unlock game modes at a terminal in the control room as you enter. Original audio has also been applied to the robots to give behavioral cues. It looks very well made, and seems to have more complex gameplay systems, if not as many frights, as Five Nights at Freddy's.
If it sounds like your sort of thing, you can download it on the official page. I've also included a trailer below, because I'm nice like that.