WebPhone
- Use WebPhone software to call any phone, including mobile phones.
- http://www.webphone.com/

Vitez Multimedia Solutions
- Maker of PicoPhone, an Internet phone application with chat.
- http://www.vitez.it/

SharpVoice
- Free PC-to-PC and paid PC-to-telephone calls. Windows 95/98/NT/2000/XP supported.
- http://www.sharpvoice.com/

Skype
- Peer to peer internet voice service. Mac, Windows and Linux versions available. Users may call landlines and cellphones for a fee; users may call each other for free.
- http://skype.com

SipTelecom
- Free Internet Phone Numbers (iPN) allows you to get video conferencing calls from your web site and email messages.
- http://www.siptele.com/freeipn.html

Paltalk
- Operates with different chat systems such as ICQ and AIM, and enables live video calls. [Windows]
- http://www.paltalk.com/

VocalTec
- Providers of integrated communication solutions, including software to allow web-page visitors to call any telephone from their multimedia PC. A useful solution for customer support.
- http://www.vocaltec.com/

Visitalk.com
- Free calls and chat anywhere in the world with NetMeeting or CU-SeeMe. Includes voice and video support.
- http://www.visitalk.com/

World Voice Cafe
- Offers free voice chat with text and sound communications available.
- http://www.worldvoicecafe.com