Hmm, have you ever used a system with multiple monitors? It's really,
really nice to have a the extra space so you can have a web browser
and text editor side by side and still have room for a handful of
xterms. I added a second 17" monitor a week or two ago, and it's
great.
If you really want to use multiple monitors with Linux right now, you
don't have many choices. You can either use a commercial X server or
hang the monitors off separate systems and use something like 'x2x' to
let one keyboard and mouse control them both. I'm using x2x and it
works fine, although I wish there was a way to switch screens without
using the mouse. It's not exactly what the original poster was asking
about, but it is very useful.
There's been some talk about adding multihead support to XFree86, but
it hasn't happened yet, and may not for quite some time unless someone
steps up and adds the code to make it work.
Scott