Quote Originally Posted by Kaiser
If you let the engine fully over-rev itself then it's possible that your valves floated and impacted the cylinders. This could have caused them to beat against the head and pushed against it, blowing the head gasket and possibly breaking some of the head bolts in the process :-\

Over-revving the engine woulda caused damage, but I dunno if it would have caused all the coolant to leak out...did you smell Antifreeze when you stopped, or see it dripping? It may have been dry before it happened, you should also check the lines at the bottom of the radiator and block to make sure they are still in good shape, but I have a feeling that your car won't start for a different reason.
ok... WTF? what you just described has nothing to do with valve float... maybe you meant dropping a valve? and the process of lifting a head could indeed cause all of the coolant to leak out... however you could've just simply blown a radiator hose or the seal around the end tank of the radiator...