The first time I watched Irreversible, I had to stop halfway because the crazy camera work was making me extremely ill.
I also once almost threw up after visiting a gore site when I was thirteen. That was my first and last ever visit to those kinds of sites.
One time, I almost got heat stroke after I fell asleep in the sun for about five hours. That night sucked hard and to be honest, it's a miracle I didn't die, considering how miserable I felt.
And once, after a rousing round of Slaughterhouse (two teams of aggressive grown men, two inner-tubes, two soccer balls, one big circle, everyone on their knees and no effing rules besides ball goes in inner-tube) at this camp I worked at, one of the other councilors promptly threw up on the beach, though we were all feeling it.