1)   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.

 2)   BeyondPhone 2.4.1.0
BeyondPhone is future of internet telephony. You can make substantial savings on every outgoing call. Call anywhere in the world from your computer. For high call clarity and low calling rates , for details visit our website http://beyondphone.com