Is there any javascript ssh client?
Not in JavaScript that I know off, but you can run a python script on the server that will provide you with an ssh-shell in a browser.
GateOne
Not pure HTML5, but there are other online (html/js/css based)
- Firessh
Webshell(no longer resolves as of 06/2016)sshterm(no longer resolves as of 06/2016)