RPG Now has a free horror RPG module called Dead of Night: Night of the Santa Claws. It’s designed for the Dead of Night RPG, but no doubt could be modded for any other system.
Danger 50,000 Volts: The Zombie Edition is a hysterical send up of both zombie movie culture and those second rate documentaries that show up on cable.
Cheapass Games offers Renfield, a card game about parts, tools, gravestones and “yummy delicious bugs.”
Robet Spears has some instructions on builidng a burial mound in 25mm / 28mm scale. It’s the perfect thing for a horror game.