Seeing plenty of comments on here about not wanting to experience a kidney stone, and while I've not had one, I knew someone who did. He was pretty much the 'hardest' guy I know - very manly, did lots of stuff like rally driving, etc. He used to do motorbike racing, and in once race he fell off and his fingers got caught between the chain and rear sprocket - leading to damage which meant surgery and a permanently disfigured hand - but he still managed to get back on the bike and finish the race. That's the kind of guy he was.

This man described passing a kidney stone as the 'worst pain imaginable', so I can only imagine what I would think it was like... Since that day I've made sure I drink plenty of water.