As the prices of monitors continue to plummet, many people I know are taking advantage of having a two monitor setup.  UltraMon is a great utility that extends your Windows screen across as many as 10 monitors (just imagine that for a second...), thereby increasing the real estate that you can work on at any given time.  UltraMon is different than Maxvista in that the later is best suited for those that have multiple PCs laying around.  UltraMon doesn't require that the additional monitor be hooked up to its own PC.

I've been using UltraMon for some time with my convertible Tablet PC in a very effective desk configuration.  I have UltraMon setup to extend my desktop to an external monitor, and I keep my convertible laptop in tablet mode.  I connect an external keyboard and mouse, and instantly I have the beauty of operating in both tablet mode, and traditional mode from one laptop.

Features of UltraMon include a smart taskbar that recognizes which monitor an application is on, so you don't have duplicate task bar buttons at the bottom of your screen.  UltraMon also lets you choose either a different graphic for each monitor, or the ability to stretch one wallpaper across attached monitors.