1) Choked on a tortilla chip when I was 6 years old.
2) I'm deathly allergic to peanuts and tree nuts. Had maybe 20 reactions in my life, but only one was near life threatening. It was delayed onset, which was unusual. I was on a business trip, and running on a treadmill in the hotel gym about an hour after eating lunch at the buffet. It was over 100 degrees outside, so I decided to stay indoors (which ended up saving my life). After running for about 15 minutes, I felt a strange tightness in my chest. I'm not usually one to cut a run short, but I could tell something was very wrong. I started walking back to my room, got about 10 steps and all of a sudden went into full-blown anaphylactic mode. Collapsed on the ground, and managed to gasp instructions to my friend (another thing that saved my life, if he hadn't been there I'd have been a goner) to get my epi-pen from my room. By the time he returned 5 minutes later, my airway had been completely restricted for about a minute, and I was lapsing in and out of consciousness. Somehow managed to administer the epi-pen, and a few minutes later the ambulance came and got me in an oxygen mask. Still have no idea what it was I ate.
3) Various close calls with cars while running/cycling.