i had the exact same shit happen to me on the matanuska glacier this summer...luckily i just faceplanted after falling 10 feet..no crevasse. maybe we should start carrying our prusiks differently? i was kneeling, and when i stood up the loop from one of my prusiks caught on my crampon, turning me into the amazingly retarded freaky robot, toppling over and sliding down, realizing at any moment it was gonna start hurting a lot...
Yeah, me three. Same think...a daisy chained piece of cord came undone and caught when I bent over to do something. When I stood up I went tumbling. Yay...real fun.