When I had a second monitor on my Windows laptop one of my must-have apps was Ultramon. A great little application allowing you to have greater control over your programs, wallpapers and extends the start bar across each monitor. The thing I really liked was that you could assign hotkeys to move your program windows between monitors. Something that would prove to be quite handy (especially when Windows would screw up and throw programs to a monitor that didn’t exist when you were in single monitor mode).

For Mac users, a new app called SecondBar, which is still in its early stages, is the beginning of something similar to Ultramon. At the moment, it only duplicates the menu bar over one other monitor, and according to the developer, only works for some programs. A recent mention in LifeHacker has sparked development again so it’s definitely something to keep an eye on.