1)   RinGo 0.6
Make voice calls from any PC in the world. Free voice connectivity with Internet users. RinGo allows you to make calls from any place in the world from your PC without the use of PSTN (traditional telephony provider) for local and international calls

 2)   sharpVoice(tm) Client 6.0
sharpVoice is a internet telephony program that enables free PC-to-PC and inexpensive PC-to-Telephone voice conference calls even with slow internet connections.