The new generation VoIP telephones that is offering customers ultimate convenience and economy has been instrumental in providing businesses a virtual office. The advantage of Virtual PBX Systems is that a business house does not need any additional hardware or equipment for carrying out the functions of the PBX. The hardware is maintained by a VoIP provider, which means that small businesses could get the benefits of the feature of high end PBX at no additional cost. Whichvoip.com has reviewed the operations of the virtual PBX service providers to enable the small and medium businesses select the appropriate PBX provider.