So I wanted to make a Gourd Banjo but didn't have the patience to grow my own gourds. I spotted a wooden salad bowl in an antique shop here in Western North Carolina and came up with this. I recently sold this banjo on Ebay to a collector of antique banjos and "inventive" designs in England. After receiveing the banjo he let me know via email that it is a "stunning banjo - obviously very well made!"
Below is a video explanation and a video of Isaac Deal playing the instrument. There are also a few close-up photos below the video.