Google Voice is a phone service provided by the makers of Gmail. It is an extremely well priced and competitive phone service that has VoIP rates which are literally pennies. In fact, if you are in the USA then calls are completely free throughout North America. The service also offers a number of other perks, such as voice transcription, conference calls, SMS to email, voicemail and even voicemail message to email services.
Inter2fone has it Headquarters in Miami, FL USA and has regional offices in Equator (Southamerica), and Switzerland (Europe). Was inittialy formed like a division of FIX GROUP to attend VoIP services for the Latinamerican Market.