Ive had a close one myself. I was swapping the tranny in a grand marquis for my parents, and my dear STUPID uncle rolled it up onto the ramps for me. Unfortuatly, he half-engaged the park(anyone with a crown vic/grand marq knows the shfters suck) and i blocked it, jackstands under the frame and hit the e-brake. I crawled under this thing, and started loosing the crossmember bolts. Next thing i knew, the car started getting closer. I grabbed the side and basically threw myself out. I stood up, and turned around to hear SNAP(ebrake cables), Crunch(jackstands sinking) and kind of a grind(blocks moving out). when it fell to its level position, it sat about 2 inches off the ground. Not Cool!