I've told this story before, but I've been running 2 monitors since 2007, and when one of them broke and I was forced to use 1, it was an absolute nightmare for me.
 
I'm hoping to acquire a 3rd at some point, along with a new GFX card

I had 2 monitors for a while, an ancient early day 19" sony LED, and a more recent 24" Acer gaming monitor.
 
But for most of that time I had a tiny desk. Until I took a trip to Ikea, and then this happened:
 
http://forum.cakewalk.com/Everyday-I-wake-up-to-heaven-m2971201.aspx
 
I'd love to have a third monitor, but then I wouldnt be able to see my glorious uber PC behind it ....
 

Focus is, or isn't the issue. I have a hard enough time trying to keep track of the pointer on one monitor. Two was a nightmare.

OK all I have to say is what took you so long?????? LOL 

No joke, John, that's what I'm asking myself!

Guitarpima - I have to say - you are the first person I've ever heard that didn't like a second monitor.  I suppose I occasionally lose sight of where my cursor is, but rarely.  I use two at the office and on my DAW.  When I have to work on my laptop (web development), I feel claustrophobic.  I use a lot of shortcut keys (like Alt-Tab to switch applications), but it still isn't the same as being able to just look to the right to see the results of what I changed on the left.
 
For those who an issue with application focus, do yourselves a favor and get a device like a tranzport or even the little transport section that is on a keyboard like the PCR-800 (A800) as their controls work whether Sonar has the focus or not.  I rarely use the actual keyboard for start-stop-record-rewind-play-undo, as they are handled on 4 different devices around my setup - my countour Shuttle (only when Sonar is focused), the PCR-800, the Tranzport, or the BCF2000.
 
For what it's worth.

I love having two monitors! Lately I've been contemplating a third, ...... if I can figure out where to put it!!  lol

Blades, great post. 
 
Tip. Speaking about focus. In the old days there was a function that was either added on or in later windows incorporated called X mouse. Today it can be found under the Ease of Access Center then goto "Make the mouse easier to use".  Select "Activate window by hovering over it with a mouse."
 
If you have never used this before it may take awhile to get use to it but it is a wonderful way to deal wit focus issues. 

sharke
... However, I could really use a third screen for the desktop for when you're ...reading an online tutorial or a PDF manual or watching a video tutorial. It kind of sucks when you have Sonar on both screens and you're trying to read some instructions and every time you click on Sonar to try something out, the manual disappears. 

For the reason you point out, I have two 27" monitors and use an iPad for reading all my manuals, (stored in "Good Reader") and to view online tutorials. The iPad also stores all my sheet music (using "forScore")
 
Walt

Download an app called cursor lock if you have problems with using a mouse across two monitors, it will lock your cursor to the main screen, but I think its only for games.

Really not sure why anyone would have a problem with the mouse in windows on multiple monitors tbh.