Gizmo is a project similar to Free World Dialup in that it is a standard-based software Voip phone system. It allows you to make free phone calls over the internet using a closed-source client they have developped but since it is based on SIP technology, you can basically use any SIP phone you want. It also hooks into other SIP providers like FWD.

Website: http://www.gizmoproject.com/

See also

• Asterisk settings gizmo