I did lots of OBDII stuff on mine...here is the tool I used. Very useful and you can even buy all the chips to make your own embeded one. Less to hide.
http://www.scantool.net/

If you are handy with coding, its super easy to build your own interface. I had my own C# application running on my cell phone within an hour that talked to my scan tool wirelessly througha bluetooth-serial adapter i bought on ebay for $15.

Awesome PC! I've been looking around to do something like that. I'll have to look more into what you did!

 

I'll be glad to help you with anyquestions you may have regarding this PC