Horde of the Dead is a free print-and-play game of zombie survival.
Horror
Ray Bradbury Theater On YouTube
Back in the 1980s, science fiction/fantasy writer Ray Bradbury write 65 episodes of a Twilight Zone/Outer Limits style anthology series.
The entire run of Ray Bradbury Theater is now on YouTube.
Lamentations of the Flame Princess RPG
Lamentations of the Flame Princess is an old school RPG of “fantasy adventure and horror.” The link is to the free version without illustrations. The illustrated version apparently has some rather adult and disturbing illustrations.
Call of Cthulhu Quick Start Rules
Call of Cthulhu is one of the great role playing games. There is a set of free quick start rules available on RPG Now.
Shaun of the Dead Card Game
Shaun of the Dead is free card game based on the very funny movie of the same name.