To see Webmin in action, check out the demo server at :
The login is demo , and the password is demo.
There is also a demo of Virtualmin Pro (which is built on top of Webmin) available at :
The master administrator's login is root , and the login for a domain owner is demodomain. For both, the password is demo.
Below are some screenshots taken from regular Webmin, accessed with KDE's Konqueror browser (as it can be easily automated).