Elastix is a complete GNU/Linux distribution with Asterisk, Zaptel, Openfire, Postfix and many other free software packages. It has a user-friendly interface that integrates the best tools available for Asterisk-based PBXs, as well as its own set of utilities which allows the creation of third party modules. The software was created by PaloSanto Solutions, an IT company from Ecuador, and released to the public for the first time in March 2006. Elastix has a good support for telephony hardware … you can see the complete list at their hardware compatibility list.