Yahoo today said it is launching a service in the U.S. that allows users to make phone calls through its instant messaging software for 2 cents or less to the top 30 phone markets worldwide, including the U.S., reports Reuters. The Phone Out service also allows calls from computers to regular phones at varying rates to some 180 countries. The anticipated move attempts to undercut rates offered by eBay's Skype service.

Though initially the focus is on offering cheap phone calling for computer users, the battle will likely shift to mobile phones, analysts said.

Yahoo's rates include a $2.99 fee per month, writes USA Today, adding that the service won't charge to receive calls. MSN is now testing a PC-to-phone service, and AOL says it will have PC-to-phone calling available later this year.