Blogroll for tag pbx
Asterisk - An open source PBX running on Linux
Trixbox - A easy to install and configure business class IP PBX system based on Asterisk (formerly Asterisk@home)
Aikido, Retreat or War. What’s your Microsoft strategy? (Alec Saunders .LOG)
SIPfoundry - A open source SIP based IP PBX, Nortel's product is also based on this
AsteriskNOW - A customized Linux distribution that includes a full Asterisk system for home
A $10 Linux Answering Machine
How To: Building an Embedded Asterisk PBX