I am impressed with the web-based jscl repl. Most Lisp web repls are for toy Lisps. I was so charmed that the first form I tried in JSCL, (make-package "FOO"), worked that I didn't mind that a lot of other stuff hasn't been implemented yet. I want to help hack on it to make it better!
A bunch of people have forked it on github to add more and more functionality, and I think jscl will just keep getting cooler. Good job, David Vázquez and contributors!