At DDA, we use many different software programs while working on our projects. Because of this we are provided with two monitor screens to enable us to work with speed and efficiency in yet another area.
When working on websites, I typically have Dreamweaver and a web browser open so I can easily refresh and view the changes without having to minimize or restore any windows. Two monitors is almost essential for efficient work in Flash when it is an actionscript heavy project. One window can have the main program with stage and timeline open, while the other window can have the actionscript window open. Then you can easily switch between different movie clips or frames that contain actionscript and not have to keep hiding the code window. You will also be able to have the code window at maximum size and still be able to see what movie clip or level you are on at any time.
Working in 3D with Lightwave also promotes the use of two monitors since it uses two applications. One application is for modeling and the other application is for the animation. Now we can work freely with both applications open.
I recommend getting another monitor for those working with only one. You will be amazed at the advantages it brings. I have never had two monitors until I started working at DDA and I now can’t imagine working without them.