Saw 1 surprised me a lot when I saw it, and I liked it very much. I have seen one of the sequels, number two or three (the only scene I remember of it is someone digging around in a hole filled with syringes), and it was absolute shit.
There’s one film with Val Kilmer that reminded me a bit of Saw and I liked a lot, Mindhunters.
House of Wax was very good, too. The idea of being in a far away place full of lunatics you can’t escape and no one to come and help you has always pressed my buttons. That’s why I love movies like The Thing, Wrong Turn (called Exit 666 over here) or 30 days of night. The scene in HoW where the guy pulls the skin off his pal’s face was EXTREME.
Again on the subject of violence against animals vs. sexual violence or child abuse in movies, I can’t say why violence of one kind bothers me that much, while other violence just makes me shove more popcorn in. It’s even the same when I play videogames: in one of my ten favorite games ever, Carmageddon 2, running over and crushing old grandmas made me laugh with joy, while at the same time I always tried not to run over any of the dogs that ran around the streets, and hitting one and hearing its scream of agony made me cringe.