A while back, there was a thread about how to drive two monitors to
increase the display size of the desktop. As I recall the conclusion
was not easy or perhaps even possible to do. The July issue of
Windows Sources has a review of an Appian Graphics Jeronimo J2 board
that will allow just what was wanted--to spread the normal screen view
over two monitors. The price is a bit high--$590 and performance not
up to Matrox Millenium standards, but as the article says--cheaper
than a 21" monitor and the drivers seem to work.