The Devils Rejects.

House of 1000 Corpses and 3 From Hell are alright, but Devils Rejects is my favorite. I can't hear Midnight Rider or Freebird without thinking about this movie.

You like em tongue-in-cheek? You might try Chopping Mall (1986). Shopping mall management invests in a killer robot security system. A group of horny teens decides to spend the night there, but a lightning storm takes out the main killer robot controller! It's funny, a little gory, has topless men and women, and it's hilarious. A spook night favorite of mine.

Let The Right One In

day of the dead is fantastic. perfect build up and release. watched it with a lot of friends and damn we went crazy for that ending

The 1922 Nosferatu.

Midsommer is my favorite. A slow, realistic slide into horror.

GYO Tokyo Fish Attack. Body horror is a great genre that doesn’t come around very often without looking kind of cheesy so it helps being animation.

The Fly is another great example of the genre. Such an excellent movie with a sad ending to top it off.

Not my favourite but Sleepaway Camp is an absolute classic of so-bad-its-good 80s horror with an unforgettable ending.

The original Night of the living Dead is way up there for vanilla zombie horror. 28 days later for modern zombies.

Thankskilling and Jack Frost for B movie holiday horror.

Society

Army of Darkness.