Anyone played "The Ship" ? If yes, you will recognize many of its game mechanics in a Bloody Good Time. It's a 1st person shooter based on the source engine and has the same graphical style as Team Fortress 2. Aside from usual game modes like Deathmatch it features a very interesting game mode called "the hunt". There are rounds of usually 3 mins in which you have to find your quarry and try to kill him/her. But you have to be careful because there are guards which will knock you down with their taser if they see you doing anything criminal (like wearing a weapon or killing other people). In addition there is also someone you wants to kill you.
If you are interested here is a nice gameplay video showing some of the game mechanics (including weapons, items, traps, etc.):
http://www.youtube.com/watch?v=K9HEVeSzGJY
Bloody Good Time was released on steam and it costs only 4,49 $ (-10% atm). It brought me a lot of fun for its little price. Sadly the developers of this game (Outerlight) made a publishing contract with Ubisoft and apparently they were screwed by them (no bloody good time anymore...). Their office is gone, the devs were laid off and their team consists now of one single person who is working for free and hoping to get some money for the hard work they had invested in this game. So if you like some of the gameplay videos on youtube I highly suggest to buy it. It's really worth it.