My previous set up was a desktop, 2 screen (17" & 19") monitors. The upside of this set up is the number of tables without any overlap and the ability to have extra things on the screen without any risk of misclicks like IM's, Holdem Manager Pokerstove etc. The downside is that its damn unsociable.
I recently purchased a 19" Compaq laptop for about £350 which has allowed me to play poker and spend the time with the missus. Same thing different location but she feels like im spending time with her. Fair enough. This, in turn, has led me to lay around one and a half the amount of hands than I usually play a month which has also led to my record month in profits.
Its almost month end so I best not speak too soon. I will post the graphs/stats in a few days once I lock the profit in for Jan.