1)   3CX VOIP Phone for Windows 6.0
Free VOIP / SIP phone (softphone). Use your PC as a phone. Works with any SIP / VOIP provider and phone service. Easy to use interface to transfer, forward calls or review history of calls. Free download from http://www.3cx.com
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 2)   4PSA VoipNow Professional 1.5
4PSA VoipNow is the leading Linux IP PBX server software designed for providing hosted PBX services and enterprise VoIP. Advanced features like IVR, call queue, callback, calling card and conference are available.
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 3)   3CX Phone System for Windows Free 6.0
3CX VOIP Phone System FREE edition is a SIP-based IP PBX developed for Windows. Easy to install and configure, it eliminates phone wiring and allows hot desking. Lowers call costs via VOIP providers & eliminates vendor lockin. Download FREE edition!
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 4)   PBXPress Live CD Demo 1.1
PBXpress is a voice over IP (VoIP) replacement of traditional PBX in the era of the Internet. All of your phones are connected and provisioned via an IP network, your phone calls are always recorded and connected at a fraction of the usual cost.
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