Voice over IP is one of the “next big things” in technology and is starting to get some play in the mainstream and technical press. The main effect I’ve found is if you call some tech support lines, or catalog call centers and notice that the voice quality is bad, you may suspect that they’ve installed a VoIP system. Like cell phones, it turns out that voice quality is only one of many parameters that can be evaluated, along with cost, function, and configurability.
One of the best ways of playing with VoIP is to get an account with Free World Dialup.
I’ve created a VoIP Resource Guide with pointers to equipment vendors, software developers, and theory behind VoIP. It is a little long in the tooth, last revised in June 2004, but I did a quick check of several links and many if not most entries are still applicable. A visit to the VON trade show in Boston in October of 2004 also confirmed that there still needs to be some work done before VoIP will be fully practical.