In pre-production we worked with Background Images doing projection screen tests with our graphic design layouts.  Working with Chris Kieffer our lead playback designer on the film, it was my job on the MTA Headquarters set to build the system that would interactively play the graphics on the 5 2k projector screens acting as one large computer display by running  5 different computers in sync. It also had to be completely interactive so that we could trigger them based on the scene and actors movements.

Below is a picture of the inside of our control room at the Kaufman Astoria Studios in Queens, NY.  We had 5 workstations running custom software synchronized each with their own external RAIDs for smooth content playback.

On the video chat sequences in the film we used iChat on 2 MacBook Pro laptops.  I needed to work as Tony Scott's camera operator using one of the laptops with it's integrated camera as the shooting camera and capturing the chat video on the other.  

We then used that captured chat camera footage for playback on set ...

as well as using it in post VFX shots.

I also needed to build the laptop computer UI screens...

and the news and stock information screens for the MTA Conference room scenes.