After a colleague left at work, I briefly "acquired" their monitor and had a fairly regular dual monitor setup. This was great in many ways, particular as I was debugging some OpenGL code at the time, and it allowed me to have the source and app open at the same time. There were a few issues though:
Anyway, before long a new guy started, and the second monitor was needed again. I did however find a spare screen, that was smaller than my main display, and experimented with using that as a second monitor. I finally settled on the setup shown in the photo, with the second display rotated. This has the advantage that it takes up less space on the desk, and makes it much more obvious to know what to do with each - most tasks just seem to naturally fall into either "landscape" or "portrait".
This requires installing the ATI drivers, and extra control panel, and makes it weird to VNC into the box, as the screen area is non-rectangular. I'm still waiting to see how PC Duo copes with this, but I haven't needed IT "support" for a while.
(apologies for pixelating part of the image - just playing it safe with commercial sensitivity)
(apologies also for running windows - I do run cygwin and NTemacs a lot - it isn't the best when it comes to dual monitors... I think it's window placement strategy seems to be "put child windows as far as possible from the parent window" or something along those lines... whoever decided to make the window manager a separate replaceable process in X is a genius, possibly even a small god, in my book)