Not to mention (well, blew that one as well) but how the 'container' made of such a thin material, can hold so much pressure. We recycle our aluminum cans, he11, have used the aluminum in a project or two (and a few repairs where a flat, slim, cut-down piece of metal was needed). Funny how you remember that stuff is SUPER SHARP, just AFTER you accidentally slice into something your not supposed to. I wonder what process (in the brain) so vividly recalls things when PAIN is introduced? One good thing, the cut (or cuts, especially when a jerk-back impulse isn't suppressed) usually is clean. I hear they do heal a lot more quickly than say, a jagged cut?