"VOIP" stands for Voice Over The Internet Protocol -- and means using your internet connection as a phone line.
"When I say 'features,' I'm talking enhanced calling plans, video conferencing, conference calling, three-way calling, caller ID," explains Cedric Guillory of NetTalk. "We also have a new feature called blacklisting, or call-blocking , so, for annoying calls that you choose not to receive, you can also set your device up to refuse those calls."
Guillory of NetTalk showed us how the Duo works. You plug a phone into the device and then plug the device into your computer or router. Once you complete the registration process, as long as you have high-speed internet, you're ready to go.
Guillory adds, "You also get to port your existing phone number. So if you have a home line that you're used to, and that you've had for years, you can take tha number and now add it to where it's controlled through that device."
The original, plug-in NetTalk Duo costs $50. A version that connects to WiFi costs $70. You'll have no additional bills the first year, and pay $30 a year after that for up to 3000 minutes of domestic talk each month.
A 60-country international plan costs $120 per year. But if you're calling overseas to someone else who has a NetTalk device, you don't need to use an international plan.
MSN Money runs down some other money-saving apps and systems you might consider, if you click here.