Just now saw this one. I'm pretty interested in those little fellas, as you'd think, they really only have one purpose. There was a great write up and video over at Gunblast on thse:

Charter Arms "Boomer" 44 Special Five-Shot Pocket Cannon

He states he has some around the house here/there...pretty good idea, be it a bit on the expensive side.

The only thing keeping me from seeking one out is that I'd really only want one with Crimson Trace grips on it...and those silly things are darn near as much as the stinking gun at $190/set. Well...not really, but you get the point.