I know you guys are thinking about practical uses, but I would like one simply to hang on the wall, take company out into the back yard, blow up a couple watermelons, go back in hang it on the wall, drink a couple shots of whiskey and exagerate about how much bigger an explosion the watermelon made than we ever expected.
Did you happen to see the airsoft post? I have to try somthing just to try it. Half way through that build I was thinking "what a complete waste of time and money", it cost way more than I ever thought it would and is pretty much useless except for a short show it off blast of plastic ammo and a conversation piece...but it was interesting to try it out. Besides, it looks pretty cool mounted on top of my sons RZR.