If you're a regular then you know, I'm a big fan of Evil Dead and Army of Darkness. Though I occasionally miss a week or so, I have a regular feature called Ash Wednesday. Those posts are geared towards the Army of Darkness rpg, but that doesn't mean it's the only one that would benefit from new material based on the films.
Updated at based on reader suggestions.
The Evil Dead
The Evil Dead (also known as Deadites) are a horrifying combination of un-dead demon. In the loosest terms the Evil Dead are bodies possessed and/or animated by a Kandarian demon.
Evil Dead: Init +1, Atk claw or bite +5 melee (2d4 plus possession); AC 12; HD 5d6; MV 30'; Act 1d20; SP deadite possession, type I demon traits, un-dead traits; Fort +5, Ref +2, Will +2; AL C
A victim of a Kandarian Demon's bite or claw attacks must make a DC 12 Fort or Will save (player's choice) or become possessed by a Kandarian demon in 1d6 hours (effectively becoming an npc until killed or demon is exorcised). Sunlight will drive a Kandarian demon from it's host.