Skype
For those who haven't heard Skype is here! Skype allows you to call people over the internet as if you were dialing their number on a phone and it's free. Not only does it allow you to call people on the internet but you can also call people's land-lines or mobile phones. And there's more... Skype have just released a beta of Skype In allowing mobile phones and landlines to call you on Skype. Brilliant. Via Engadget
www.skype.com