Obscure Lisps: EuLISP (https://github.com/Henry/EuLisp) and ISLisp (for example, https://github.com/sasagawa888/eisl)
Then there is PicoLisp, lfe (Lisp Flavoured Erlang), lux (https://github.com/LuxLang/lux), Coalton, Janet and newLisp if you want something that's actually maintained.
I also heard about Flesh: https://gitlab.com/whom/relish Flesh/relish is a Lisp that can be used as login shell, it's a bit similar to scsh or that one guy who used Clisp as his login shell ("CLASH" or CLisp As SHell.)
More can be found at https://github.com/dundalek/awesome-lisp-languages
Just stumbled upon Chialisp: https://chialisp.com