was waiting on a wide base rear sprocket from tarty so whilst wainting took a 17tooth out of a sram cassette.  After couple days of riding, went to just drop off a wall on my way into town, rear sproket snapped (same effect as chain snap) and went head first towards the ground. Just managed to get my hands in the way of my face and got away with bruised thumb muscles (which is a right pain in the ares!)   About 3 years ago, was riding Combe Sydenham DH track in the wet and over-shot the road gap that leads into a meadow section. landed and didnt have time to react for the berm that followed, went straight over it and ditched the bike mid-flight. Hit the wet grass on my back and proceded to skim down the hill about 100meters, like i was on a water slide. Was the most fun bail i have EVER had.