(I work on a single monitor setup).
Dual monitor is superb during coding and debugging. That nasty gui you are debugging is always visible (you drag it on the other screen) and when you hit your breakpoint you can still see it nicely. It helped me a lot in my M$ devstudio gui projects, otherwise the IDE get's focus on the breakpoint or the code you are stepping through and you don't see the GUI window anymore since it's behind the IDE window.
And it is also very nice, to have on a second monitor a Firefox open on the CB page, forum page, so you can check from time to time for the new information.
;-)
I am kinda missing Yiannis's today's changes (well I see them in svn anyway).
Maybe we should buy Yiannis a second monitor for x-mas ...