https://github.com/redhat-developer/openshift-vagrant (requires read authorization) provides a VM with OpenShift where anonymous authentication is supported, i.e. any username will be accepted (a user will be created on-the-fly) and there's no check on passwords.

However the connection wizard doesn't allow blank/empty passwords. Also it currently trims whitespaces from passwords. So one has to type in a dummy password in order to get through authentication.