a non-exhaustive list of active systems as of 2019
from Pubnix History Project
Public Access UNIX Systems (PAUS) are a type of server that provide various services to a multi-user community. They first began in the early 1980's and continue today. Early servers ran various flavors of UNIX, hence the name Public Access "UNIX" Systems, but later generations saw a large mix of Unix-variants and, of course, GNU/Linux. To recognize the many different operating systems online today, these systems are increasingly referred to generically as "pubnixes".