So this is what happens when your fun hobby project gets featured on Hackaday. I guess I've had my 5 minutes of fame and now I have gone back to obscurity. It's interesting to note that this traffic spike to my YouTube videos only netted me a couple of bucks in revenue so I'm still several years away from receiving my first $100 payout. I'd better not quit the day job just yet!
On the plus side, all of this attention did result in me selling more than a dozen of my octasonic boards, which was pretty neat. The best part is that some of them are going to be used in a public art project next month and that's much more satisfying than making money from this.
I suppose one moral here is that one way to sell your electronics inventions is to make a fun demo to share with the world.