Kannel - Open Source WAP and SMS Gateway
Miranda NG - Miranda NG is a successor of a popular multi-protocol instant messaging client for Windows - Miranda IM. Very light on system resources and extremely fast.
Ozeki NG SMS Gateway - Ozeki NG SMS Gateway is a powerful, reliable and flexible SMS Gateway application.
Pinger - Pinger lets you text and talk free with the people you care about most, anywhere on the planet.
KAPSYSTEM - KAP Computer Solutions Pvt. Ltd.,
Tencent QQ - Tencent QQ is a free instant messaging computer program developed by the Chinese company Tencent Holdings Limited.