I have been having a lot of fun in the last few days with Asterisk, the open-source PBX. I have an inexpensive Grandstream BT-101 SIP phone (and two more on the way) and a Digium Wildcard X100P FXO interface connected to an analog phone line.
It’s cool to bridge IP-to-analog calls, program the PBX dial plan, and generally do all the cool stuff that used to be the exclusive domain of the guys who set up PBXs at big companies. Actually, I can do a lot of cool stuff that is hard or expensive to do with traditional PBXs. For example, I can use Asterisk’s IAX2 protocol to connect remote offices so that extension 1004 here can ring a phone at another office. Or I can have an incoming analog line ring my office phone and my home phone so that, if I’m working from home, I can pick up work calls as if I were in the office.
For those who are interested, I have built some Asterisk RPMs for Red Hat Linux 9.