ssh to applicant@register.public.outband.net
instructions at https://www.public.outband.net note that it's ip6 only.
It is pretty pointless, nobody needs or wants a unix shell account in this day and age. But I had fun setting it up, it started as an exercise to see what a shared multiuser postgres install would look like and got a little out of control. My current project is getting a rack of raspberry pi's(6 of them in a cute little case) hooked in as physical application nodes.