Make FREE pc-to-pc and pc-to-phone calls over Internet and ISDN/PSTN and SIP network. PC-Telephone is a powerful communications software that enables you to exploit the full communications potential of the Internet and public telephone networks ISDN/PSTN. PC-Telephone makes possible to use your computer as internet telephone, ISDN phone, answer phone, fax software, voicemail client and more.
From the developer: "Make long distance and international calls with Freecallme PcPhone. Download the PCPhone application, then click the 'Get an account' button on the top of the application. This takes you to a sign up page - scroll to the bottom of the sign up page to select the 'Free Trial'.Freecallme PcPhone provides you with a real phone number that can be called from any telephone in the world. Calling this number lets your SIP phone ring – anytime, anywhere.We have new features, including inbound service, unique telephone numbers, and voicemail. You may select the area code for your number or get a toll-free number, and anyone in the world, from any telephone, will be able to call you! When you are online, your computer will 'ring' and when you are offline, your calls will be sent to voicemail.""It works . . ."We have downloaded and used this to call from Buenos Aires, Argentina to the US and Canada. It connects about 70% of the time but receiving incoming calls is still something we are working out with the Customer Service which is responsive at least. Will be a great service once they develop further. Will continue using in hopes of improvement.
 Pentium 266 MHz PC* or higher (400 MHz recommended)
 Minimum of 32MB of RAM (64MB recommended)
 Windows 95/98/NT/2000/ME/XP
 Windows-compatible full duplex sound card
 Microphone and speakers, or head/handset
 Internet TCP/IP connection
 Connection Connection speed of 33.6 Kbps
 Freecallme PCPhone dialer.