A feature like this is fantastic, but I'd like to suggest an improvement. Allow VOIPo subscribers to dial into these numbers, and give them the ability to place outbound calls (domestic or international) billed to their VOIPo line. One way to set up such a system would be to have it connect to the VOIPo number when the 10-digit VOIPo number is entered, but ask for a password if 0+ the VOIPo number is entered. Once authenticated, the user would be given a new dialtone. To keep things simple, I'd recommend using the voicemail password, but if there's good reason to separate the passwords, by all means...
Talk about the

factor!
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