Stanaphone

StanaPhone.com

That's the most interesting calling service I have found. Here are some of the features which they offer for FREE!

• Everyone gets a free New York area phone number (for example, Skype are offering SkypeIn which is definetely not free).
• Everyone with a normal phone can call you and even leave you a message if you are out. Yes...the voicemail is free, too. You'll receive every message in your mailbox as an attachment. If you have an account in Gmail, just imagine how many messages can you save!
  
• You can receive fax for free. When a fax is sent to your number, it is converted in PDF format (TIFF also available) and is sent to your e-mail address as an attachment.
• Of course, all Stana2Stana calls are free.
• Nice: conference server! Also free. Max. 10 callers and max. 2 hours but that should be enough for most people.
• The calls from Stana to a normal phone is one of the few non-free things but the rates are normal.
• Calls to 911 are available but only for non-emergencies.
  

They are offering a program for Windows (about 3MB) which has a look like a phone.

You can sign up here and download the required software here.

Try it! It works!

Screenshots:
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