Google Voice is a free service for GMail users.
You are provided a free phone number.
All incoming phone calls can be re-directed to your cell, home, work or other numbers
All SMS text messaging can be re-directed through Google Voice from mobile phones.
You can manage an inbox and outbox of text messages just like email
Voice messages are transcribed and stored in an inbox.
Complete integration of your mail, text, chat and voice communications.
Answer inbound phone calls from your computer as well.
The NowDox support team can help you setup and configure Google Voice for your needs.