I've pushed a cork down a bottle with disastrous results - I don't recommend it.

Another time I was in a limited service hotel with no bar, so no place on the property for a corkscrew. I unscrewed the metal hook from a wooden hanger and used that as a makeshift corkscrew. It worked, after a few tries, but I did end up with a few chunks of cork in the bottle.

Wow, that is cool! Although the person in the room next to me may not appreciate me banging on the wall. I'll try that on the bathroom door jamb.