I don't mean to say that Mamma Mia! is a bad movie, just that it is a really bad movie to accidentally find yourself at if you have been waiting for 14 months to see "The Dark Knight". Mamma Mia! might actually be a great movie. I am just never, ever going to find out, if I can possibly help it.
As for the SAW franchise (they really need a 5th one?), this story inspired their mention in this strip.
This is what Julie Benz, one of the film's stars, had to say about her experience:
"These 'Saw' films are very psychologically terrifying, and it really affected me on a very deep level. I'd go back to the hotel and have nightmares about the movie, not actor nightmares — like 'Will I be able to perform?' — but about stuff going on in the film. I didn't think it was going to affect me like that. I mean, I was there on a set. I knew it was make believe, knew it wasn't true, and still I was getting really scared. They had a bucket on standby because I was really getting nauseous over things I had to do. I've never had that reaction to a movie before. I was always able to turn it off. But there were moments I actually forgot I was shooting a movie and really did think something awful was going to happen." (emphasis mine)
The producers of the SAW movies have apparently pushed the envelope so far that, according to Einstein's Theory of Special Relativity, they should now actually be pulling the envelope from the other side.