Gmail team has just rolled out cool new feature which allows you to makes calls to any phone number directly from gmail interface. Calls to the U.S. and Canada will be free for at least the rest of the year and calls to other countries will be billed at our very low rates. They worked hard to make these rates really cheap (see comparison table) with calls to the U.K., France, Germany, China, Japan—and many more countries—for as little as $0.02 per minute.
Dialling a phone number works just like a normal phone. Just click “Call phone” at the top of your chat list in gmail chat interface and dial a number or enter a contact’s name.
If you have a Google Voice phone number, calls made from Gmail will display this number as the outbound caller ID. And if you decide to, you can receive calls made to this number right inside Gmail, see instructions here for the same
Right now this feature has been rolled to U.S. based Gmail users over the next few days, so you’ll be ready to get started once “Call Phones” shows up in your chat list (you will need to install the voice and video plug-in if you haven’t already). If you’re not a U.S. based user or if you’re using Google Apps for your school or business—then you won’t see it quite yet, stay tuned to see it updated for you as well soon as per the they say they are working on it.
For more info, Check out gmail.com/call
[ Source – Official Gmail Blog ]