MicroSIP - lightweight VoIP SIP softphone for Windows - Official Homepage
Developer Tools Demos | Labs | Conaito
20 FREE SIP Softphones - VoIP Insider
9 Open Source Free SIP and Softphone clients
iLink - 3CX for Windows
VoIP Softphone for windows
AlienVoIP with Windows System
15 Best Softphone Apps for Business for Windows - MightyCall
VoIP/SIP client (softphone) for Windows
Softphone para Windows Gratis •• Descarga | 3CX
Zoiper - Free VoIP SIP softphone dialer with voice, video and instant messaging :: Zoiper
9 Open Source Free SIP and Softphone clients
What is a SIP Phone: SIP Software Features & Advantages
VoIP Softphone | VoIP Soft Phone, Softphone, VoIP PDA, Wireless VoIP, Wireless VoIP PDA, Internet Phone, Wireless VoIP Softphone, SIP Softphone, H323 Softphone, SIP H323 Softphone, SIP Phone, ActiveX Phone | voip
Free VoIP smartphone app for Android, iPhone, PC, Mac, Linux, WinPhone -XeloQ
20 FREE SIP Softphones - VoIP Insider
MicroSIP - lightweight VoIP SIP softphone for Windows - Official Homepage