The main site:
http://www.smgfx.com

Here's some, theres tons from movies such as Nightmare on Elm Street 4, Freaked, Silent Night Deadly Night, various music videos and video game ads... just awesome stuff!

Some of it can be graphic or nudity but the stuff they pull off is brilliant!

http://www.smgfx.com/docs/images/bride_of_reanimator/bride_1.jpg
http://www.smgfx.com/docs/images/puma/puma_1.jpg
http://www.smgfx.com/docs/images/nissui/nissui_3.jpg
http://www.smgfx.com/docs/images/childrenofthecorn/childrenofthecorn.jpg
http://www.smgfx.com/docs/images/society/society5.jpg
http://www.smgfx.com/docs/images/toymaker/toymak_1.jpg