One obscure shell not listed is Ch, https://www.softintegration.com/docs/ch/shell/ https://www.softintegration.com/docs/ch/shell/ Ch is actually proprietary so

One obscure shell not listed is Ch, https://www.softintegration.com/docs/ch/shell/ https://www.softintegration.com/docs/ch/shell/ Ch is actually proprietary software, if it was free software, I would probably use it as my login shell. I spent some time writing scripts and customizing my .chrc and really enjoyed it. It's actually a C interpreter, but with shell features.