I found this article from Bret Pimentel’s great site.
Last summer, I spotted an old brown leather instrument case at a local garage sale. Inside was a metal clarinet. I had seen a metal clarinet once before, at a gypsy jazz gig up in Ann Arbor. I had been enamored by the unique tone it had to offer to the ensemble. With the price tag of only $50, I had to get it! I ended up having the instrument overhauled completely, for about $90. This is what first sparked my interest in this niche topic.