Is sample Delphi project based on ABTO VoIP SIP SDK for Windows that allows to quickly build SIP softphone for desktop. You can also use it on Linux system with help of Wine. The softphone can have 1-64 lines support, several SIP accounts, video and voice calls, as well as audio and video conferencing. Also it supports presence and IM chat. You can build a dialer, IVR client, or integrate it to your custom application.