Space Station 13 is a paranoia-laden roleplaying game set against the backdrop of a nonsensical, metal death trap masquerading as a space station.
Read more here.
Sunset station 13 Community
There is currently one Sunset Station 13 server, hosted by Bksparkie1. it operates a Sunset rendition of /tg/ codebase.
Download BYOND to play.
Sunset: <byond server=byond.sunsetstation13.com port=1337>byond://byond.sunsetstation13.com:1337</byond>
Check out these maps that come packaged by default in the game.