functions the same way as hamachi, i like it more because the gui, and its speed is much better, or that's what I experienced with online fighting games i've played with it.
http://www.comodo.co.../vpn-access.php
so you create a group, and invite people to join, or give them the pass/group to enter in.
If you do follow with comodo, remember to uninstall hamachi and restart your computer to avoid confflicts