I love lots of screen real estate. With my new dell laptop I got two extra monitors working directly from the upgraded docking station, but I wanted more. The solution was to install Synergy on my laptop and on a second computer and use a monitor from that second computer. With Synergy I can use the same keyboard and mouse for my laptop and have those inputs sent to the second computer so it feels like four screens.
On my left-most screen, the tiny laptop screen, I always have Outlook open and use it for mail and calendaring (is that a word? - it should be), my second screen I use for Visual Studio, the third for Unit tests and Emacs, and the fourth screen has a browser since it really doesn't connect to the laptop.
Synergy is a pain to configure, and sometimes cuts out, but for the most part it works quite well.