Or you can use the Gizmo client software which IME is excellent.

Gizmo Project è un servizio basato sulla tecnologia internet telephony service. Il punto di forza? Telefonare grautitamente a tutti gli iscritti Gizmo, cellulari compresi. Servizio valido, al momento, in 60 paesi.
Gizmo Project – Di piu

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The move is that phone operators will offer call to land lines for free. Right now in France, if you have as providers Free or Neuf Cegetel & others you can call for free from your landline to other landlines in Europe and NA. They are now combining this with ToIP services like phone forwarding to your computer (through a SIP program). Who is going to use such programs (on a computer) if you can have the same benefits with your regular phone or Wifi cellphone?

“As Skype languishes in a post-acquisition eBay abyss, today’s announcement will likely move Gizmo into a much better position in terms of number of users”

Luca

The definition of active user is meant as a way to prevent abuse, not as a penalty for people who don’t use it enough. Surely if you signup for gizmo just to take advantage of this service and never use it again, we’ll never have a chance to offer your more services (or advertising) which you may or may not be interested in purchasing, so that’s really abuse.

If you’re a Gizmo user in good faith, you’ll never have to worry about not being active. Our intention clear. We want to push all calling to free. We are not trying to trick people into a program that will change substantially in the future.

I hope everyone chooses to take advantage of this program because it’s really great. It will help everyone save money and offers a set of services that you can’t get through your cell or landline.

Unfortunately, there are a few bad apples out there that we have to protect ourselves against.

Best,
Jason Droege
President
SIPphone, Inc.

basically their business plan is as thus. gizmo isnt as popular as skype and want to build their userbase (obviously). so reward the people who have already used the service by giving them free calls (they will determine the active\not active line) and hope that excitement leads to them telling everyone and their userbase increasing. so then their (hard)core user base percentage goes down as new users increase and they use that to gauge where the ‘active’ user line is. so if you are in the top say 25% based on activity your calls will be free but the new users will have to make a number of paid calls until their activity increases to that threshold. this is why they are saying the line is really low, because most the users have been around for awhile, but if their plan works and userbase takes off the line with go up with them. guess its better to hope your call might be free, than to know your paying for it (skype).

Compare their offer to the simplicity of Skype’s offer: free calls to any US phone from any US Skype account. Period. Within a couple of days of that marketing launch, I noticed that the number of Skype users logged in at a given time was up about one million users, or 20%. That’s a pretty powerful marketing campaign.

Compared to other services like VoipStunt..etc, the biggie is the free calling of mobile number.. BUT the wording of the announcement is really tricky, talking about 60 countries. 60 for landlines, yes, but only 18 for mobile calls, and the 18 includes such populous destinations as The Vatican, San Marino, Saipan…etc.