SIP Service Provider - VoIPtalk
Offers free PC-to-PC calling in addition to PSTN gateway services.
Sign Up Here:
www.voiptalk.org/products/signup.php
SIP Configuration Settings:
SIP Number/Username:
[Your VoIPTalk Number]
Password:
[Your VoIPTalk Password]
SIP Proxy Server:
voiptalk.org
Advanced SIP Settings:
Outbound Proxy:
nat.voiptalk.org:5065