You claimed to know that you lived just down the road from me, - and I have two! ...
Running WPanorama on two screens is a must!
Running Dream Aquarium on two screens is a must!
Running MA3 on two screens is a must, (... or it will be!
).
Having one screen for a text-editor/word-document, whilst the forum etc. is on the other, - is a must!
Having two screen whilst photo editing etc, is a must!
etc. etc. etc.
..... I could go on and on!
(Be afraid, be very afraid!) ...