While Google's GrandCentral is free, it hasn't done much since Google bought the FMC/UC service. PhoneFusion One is a low-cost alternative.

In a recent review, Web Worker Daily gave PhoneFusion One kudos for offering more features than GrandCentral at a cost of only $9.95 per month.  There's also a premium service featuring VoIP outgoing calls for 3.5 cents per minute, but you may not need that if you've got a bundle of minutes.

Like GrandCentral, you tell PhoneFusion which phones should ring on an inbound call and you have the ability to transfer calls or screen them to voicemail.  However, PhoneFusion adds auto-attendantesque features similar to Wildfire, including immediately answering a caller with an audible greeting and providing a verbal screening function ("Who may I say is calling?").  In addition, you can upload your own hold music.

Configuration is extremely flexible, allowing for options to set hours for phones to be accessible, how long the system should wait for you to answer and how long to wait to accept a call, plus others.  A PhoneFusion number doubles as a fax number, with the number detecting a fax tone and sending along a fax as a .PDF attachment. 

If that's not enough, there's also support for up to five participant conferencing, visual voice mail and management of PhoneFusion options with a touchtone phone.

For more:
- Web Worker Daily reviews PhoneFusion One [1]

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