I'm not the first and many people have been using the Obi devices to do this already, but I thought I'd do it differently and use Asterisk instead. This saved me the cost of buying the Obi box and I can do a ton of cool features as well so I just wanted to Web Explainer Video Production incase anyone else was interested in the process.
Here's what you need:
1) A spare PC, laptop, whatever OR you can virtualize if you choose. (Virtualbox is free)
2) The latest version of Elastix. I like Elastix because it is the simplest way to get Asterisk up and going. It is easier and faster to install than PIAF and has everything I like about Trixbox without any of the commercialized bloatware.