Google is taking on internet telephone companies like Skype by allowing users to call from its free web-based email service.

For the moment only users in the US will be able to make calls from inside their Gmail account.

Phoning anywhere in the US and Canada will be free until the end of the year, while calls to the UK, France, China and Germany will cost 2 cents a minute.

To read this BBC News report in full, see:
www.bbc.co.uk/news/technology-11092212

Also see:

Use Gmail to make VoIP calls: Hands-on review
With Google’s Wednesday rollout to Gmail, the built-in Google Talk chat app is finally getting its own voice. Specifically, a plugin that lets you surface a dial pad so you can launch VoIP calls from the Gmail.com in-box, or from within iGoogle. The big caveat is that the service is currently being rolled out only to U.S. Gmail users.
news.cnet.com/8301-17939_109-20014734-2.html

Google Is Offering Phone Calls via Gmail
Google entered a new businesses beyond Internet search on Wednesday with a service within Gmail to make phone calls over the Web to landlines or cellphones.

The service will thrust Google into direct competition with Skype, the Internet telephone company, and with telecommunications providers. It could also make Google a more ubiquitous part of people’s social interactions by uniting the service for phone calls with e-mail, text messages and video chats.
www.nytimes.com/2010/08/26/technology/internet/26google.html