Have you seen Seasick Steve play his cigar box?
How about two hubcaps and a broomstick?
He'll play just about anything with a string on it. Here's a 2x4 with one string...
Any resemblance to Larry is strictly coincidental.
From a player's standpoint, what impresses me is the fact that he's singing and playing the slide at the same time, and both are in tune. Unless you've tried it, you can't imagine how hard that is to do.