in 1960 I was on Mount Kenya with an 8mm movie camera and a good dose of altitude sickness (can sometimes make you do stupid things) and I lowered myself into a crevasse on a rope tied to an ice-axe, and shot 50 foot of film of the light filtering through the snow and ice. I had to hold on with one hand and my teeth while I shot with the other hand. Then I found I couldn't climb up again! I managed it eventually, but could have died.
Also recently took many digital shots of motor cyclists from the back of a motor bike. The driver was doing over 160 km/hr (legal speed here is 100km/hr). I was too afraid to look back, so held camera over my shoulder and pressed the button on auto. Many shots of sky and tar, but also a few shots that came out in focus. However, dramatic and compostional qualites were pretty woeful.
I can't seem to paste pics here... not that they are really worth looking at.
Cheers,
Michel