Quote Originally Posted by ockhamsrazor View Post
Disadvantages:
  • Using mainstream graphics cards I can only use two monitors (I think)

Anything major I'm missing?
The new AMD/ATI Radeon 5000-series cards support up to 3 monitors through their Eyefinity tech, as long as at least one monitor as a DisplayPort. (Or you have an *active* DVI->DP adapter)
Many Dell Ultrasharp monitors have DisplayPort, and I'm currently running 5 windows on 3 24" Dell Ultrasharps with one Radeon 5870 videocard.