I've been having pretty good luck watching "Horror" stuff that I find on Rotten Tomatoes sorted by tomatometer made this decade with a rating over 70%. I watched Eden Lake last week and Splinter last night http://www.rottentomatoes.com/m/10010329-splinter/ both of which I found this way and then checked what people here had said and both were pretty good. I'm about to watch Horror http://www.rottentomatoes.com/m/horror/ based on its rating there. I don't necessarily agree that stuff that's 100% fresh there is great, but pretty much everything I've watched over 80% has been good.

Edit: Horror has 80% at Rotten Tomatoes and 7.3/10 but I thought it sucked.