I now have a portable 2-monitor workstation without having to buy any adapters or additional hardware (though I did have to purchase Air Display program, which is fairly cheap).
What a great program! It was incredibly easy to install and configure. There is a little delay since the screen is being sent to the iPad 3 wirelessly, but not bad at all. You have the typical second monitor choices. I highly recommend it if you carry a laptop and an iPad as it opens up a lot of possibilities.
I can now clip the lighter iPad to my tripod and use it as an external monitor for my Canon T4i and even adjust the camera settings by using the canon utilities software. When I'm done with a shoot or editing, I still have all of the functionality of the iPad, since it's an iPad