Its name is MyLivio
MyLivio was developed by a French company called INEXBEE.
Before using this service you must register on their web site (free-of-charge). When the registration is done you will get link button which you can add in your email signature (Microsoft Outlook, yahoo …), blog, web site, ebay, myspace …
If someone wants to call you on your mobile phone he clicks on this link button.
Advantages
- Registration is free and you have 10 free minutes per month (not sure if it’s per day or month *you can check it yourself on their web site*)
- Very beautiful and easy to use web site
- Fast activation (no need to wait days or hours)
- Fully compliant with RFC 3261
Inconvenients
- Bad voice quality
- Work only for French registered mobile phones
- Poor user guide
- No video support
- Web page with lot of ads
- No way to use the flashphone from mobile device or PDA
If you know other web based telephony feel free to complete the list