I successfully face planted on a treadmill today.
I was only on for about 8 minutes at 6:30 miling, having gotten off 30 minutes of elliptical (I am nursing a tendon in my foot). Was just going an easy 10 minutes or so to test it, and was wearing flats. The treadmill was a Woodway, with the comfortable but sticky rubber slabs instead of a flat belt. I went to change the incline, and the front of the flat caught the belt and threw my foot back (I think my shoe untying was also involved), causing me to lose balance and fall.
I shot off the back a good 10 feet into an elliptical machine. The girl using it at the time said "whoa, are you all right?" as I bounced back up to my feet. I was fairly smooth, and there was no pain until 2-3 minutes later when the burns caught up with me. I managed to finish 15 minutes on the bike before giving up due to a little blood drippage off the elbow and knee.
Nothing like the guy with 3rd degree burns from passing out on a mill, but I thought I would share. The most thrilling part was how fast I flew off the back - literally 10mph but it felt much faster. It was amazing I didn't break my glasses or sustain anything more than a few intense rug burns.
Also, not one person other than the girl on the elliptical that I crashed into said anything to me or came over to see if I was alright. I guess they all really needed to keep their heart rates in the fat burning zone while catching up on People magazine...