Will you be repeating the same video on each of the screens or is it one image stretched across all of them? What inputs do the monitors have? Is it interactive with computer vision or controller input or something else? Is there a budget limit? As with most things Max, there may be a few ways to do it.
The image is only one in all the screens, the monitors do have HDMI and VGA input, and I'm planning to use Kinect. The budget is the as low as possible.
My concern is to have a single input from my Mac, plug it to the external hardware and have the signal stretched across all the screens.
Matrox triplehead digital edition will give you 3 screens (up to 12 with a PC) but to be honest I'd say if its all just "one" image then just arrange a dark room and get a beamer with DVI or VGA in.
Using 12 screens to make one big screen is a very expensive solution with a lot of things that can go wrong.
Or you can rent LED wall strips (expensive) chain them together and you have one big screen.