Lamentations of the Flame Princess

Lamentations of the Flame Princess

A free version of the rules can be found here, but essentially its old school D&D - quite unforgiving, straight forward, but still fun. Lifted from the "About" section at LotFP.com:

LotFP is a tabletop role-playing game born out of the mechanics of old school fantasy gaming and the love of underground heavy metal, horror literature and film, and in fact all things strange and macabre. From inspirations as diverse as Lovecraft and Troma, Argento and Barker, the NWOBHM and the Stockholm death metal scene, Vance and Morrison, LotFP's cadre of writers and artists deliver mind-bending and merciless content for your game table.

and

The rules themselves are mostly familiar and normal. You don't read the rulebook and think, "Oh, that's strange!" Well, maybe in a few places. Anything in the actual rulebook becomes in effect normal and not weird while playing the game. The idea is that the characters are normal (for values of "normal" that may or may not be present in a fantasy RPG setting), and it's what they encounter during play that is unusual and strange and where the weird is found.