I remember a movie from when I was a little kid, it was on TV. Ya' know, before all that cable and satellite.... back in the stone ages. Anyway, I think it was called Mudman or The Mudman. It was about these people who are trapped on an island, with a monster made out of mud!
They cut off it's hand, and it just goes and gets some mud to make a new one! The detached hand also attacks them when they don't expect it.
I sure it was a crappy movie, but it scared the crap out of me when I was like 6 or something. I doubt anyone will ever see it, so I will spoil the ending by telling you the mud monster dissolves in salt, so they trick it into falling into saltwater. It turns out another kid in the neighborhood also saw it. He later told me he was so scared he went to the kitchen and took a salt shaker to bed with him!
I don't think you can go wrong with Evil Dead 2 and Army of Darkness. I'm a sucker for the campy horror movies!