I decided to do a bit of searching on Github for projects that use Chestnut. A search for "Created with Chestnut" yields a 186 projects. I didn't have time to really start going through all of them, so I filtered it down to the ones that have at least two stars, and saw what I can find.
Two look quite promising
And some honorary mentions:
WordyBird Client-side Visual English Language Analysis. Looks cool looking at the screenshot. Chestnut 0.7.0.
Easy-Does-It Optionally server backed, color coded, task management with a percentage overview. Chestnut 0.7.0.
Pogue Seems to be a game, couldn't get it to run. Clearly somebody's hobby project, still 200+ commits is not nothing. Based on Chestnut 0.7.0
Webtorrent-cljs ClojureScript wrapper for WebTorrent. Since this is a library wrapper it's a bit surprising they used Chestnut, which is more for apps. Based on Chestnut 0.13
Neat Uses genetic algorithms on neural networks. Contains an example that tries to train a neural net to play flappy bird, although it doesn't seem to learn very quickly. Chestnut 0.8.1
Do you know other cool/interesting projects that use Chestnut? Or any companies that use/apps that were built with Chestnut?