What's the best rate you can get to make a phone call? How about free? Jaduka Labs offers a free service they call earthCALLER, that will let you phone anywhere in North America for free from your PC. Using VOIP technology, all you need is a microphone and speakers or a headset to make those calls. As you'd expect, you can create a contact list and there's even several speed dial slots for often-called numbers. Call history tracking lets you know what you've been up to. A built-in speed test helps you to see whether you've got the bandwidth necessary to make calls.
Because of its reliance on ActiveX components, earthCALLER is only compatible with Windows systems, and you must be running Internet Explorer 7.