Via PC WORLD : CallingAmerica, an ad-heavy but otherwise free alternative to GizmoCall. Like the latter, CallingAmerica requires no software; all you need is your browser.
In fact, you don't even need to sign up: Just enter the phone number for anywhere in the U.S. or Canada and click FreeCall Now. You can make an unlimited number of calls this way, but each one is limited to two minutes. By registering (also free), the call cap gets raised to 15 minutes.
ooVoo is the next evolution in online communication - a remarkably easy way to have a face-to-face video chat with friends, family or colleagues, no matter where they are in the world.
ooVoo Video Chat is remarkably easy to use: easy to download, easy to install, and best of all:
it's FREE!