Re: Dual Monitors
Using Nvidia Surround or AMD Eyefinity (depends on your GPU) you can use multiple monitors as if they were one. It works with SWTOR (Proof: Reddit | Imgur Gallery)
Any time you're using an even amount of monitors however, you'll have the problem of the monitor's bezels (border around the actual screen) right in front of your face, which makes it really irritating to play as the border splits the image in half. You can combat this by turning on bezel correction, which calculates extra pixels that are then not displayed to make up for the part that is blocked by the bezel, however, this will make most of your character disappear as it is right in the middle.
That's why I only recommend this if you are planning on using 3 displays, as it will just expand your field of view to the sides without putting that massive black bar right in the middle.
Now if you actually purchase 2 more monitors (make sure they're the same resolution and physical size as your current monitor), you can go to the respective control software and enable Surround/Eyefinity, then launch the game and adjust your graphics settings. Now you'll need to activate "Enable Movable Secondary Window in the interface editor, so you can move your ingame windows and open more than two at the same time. You'll now be able to freely move around things like inventory, guild, GTN and Map windows to wherever you want, whether that be your center, left or right monitor, or anywhere in between (not recommended because, again, the bezel correction will hide the portion of the window that is behind the bezel of your screens).
Edit: Grammar Nazi