I am a fan of multi-monitor systems...

In Vista support for multiple monitors is slightly more restrictive, here's
a summary:

Multiple monitors attached to a single card - no problem

Multiple monitors attached to multiple cards with the same driver (which
normally means the same chip set family) - no problem

Multiple monitors attached to multiple cards with different drivers - no
support for Glass

or more details check out this link
[url]http://www.microsoft.com/whdc/device/display/multimonVista.mspx[/url]

also a nice tool and site for multimonitor systems is this one :
[url]www.ultramon.com[/url]