I’ve read (and written) a lot about the ongoing plummeting of telephone rates as VoIP becomes more widespread and voice becomes just another application on the network. Usually we’re talking about in-country calling, or client-to-client VoIP calling, but I’ve noticed a couple of items recently that point to a similar free-fall in calling rates for international calls as well.

First, Russell Shaw had an interesting post the other day noting that Skype had applied for a trademark on the phrase “The Whole World Can Talk For Free.” Now that very well may be just a normal business practice for a tagline they have been using for over a year, but Russell thinks its more than that and predicts Skype will open up global free outbound calling:

I envision a scenario in which Skype provides totally free outbound calling to those users who sign on for the revenue-generating SkypeIn service. Free world calling could, then be an incentive that would drive registration for Skype’s paid services.

Then today I saw the TechCrunch post Rebtel Makes International Calling Cheap and Easy about how Sweden-based Rebtel is using VoIP to offer dirt-cheap international calling.

Sweden-based Rebtel have launched a product that will allow users to dial any international number at the cost of a local call. It works by having the two ends of the call use local connections (over low-cost local calls) to a VoIP point and then bridge the call to the recipient at the other end over the net.

And just take a look at Brian McConnell’s recent post on this site about how easy it was for him to set up a global PBX using Gizmo and Asterisk, and you start getting the sense that international calling is really ripe for disruption.

I’m pretty sure that the high international calling rates we’ve experienced for years have been one of the incumbent carriers’ biggest gravy trains, but I think that train is slowing down fast. Just like local and in-country calling, I expect the cost of international voice calls to rapidly approach zero, forcing the telcos to come up with new business models or die trying.