I do notice a big difference in productivity when I have more than one monitor. I typically use my laptop screen for emails and IMs while my cinema is used for blogs and writing up posts. However, one of my friends is an animator and uses three screens daily. Needless to say, he's got a huge desk. What about you — are you a single-screen gal, or do you make the most of your desk space and use multiple monitors? How many monitors do you use?