If you're a new Mac convert and you've gone and bought yourself
a Mac mini, you've probably been
thrilled at the versatility, delighted at the simplicity, and
darned near ecstatic about working on the computer and listening to
birds chirping outside.
Yes, that's right. It's so quiet - especially compared to that
old (or even new) PC - that I can hear the birds chirping while
tapping away on my Bluetooth Apple keyboard (clearly an amazing
feel in a keyboard!).
When it came time for me to expand my desktop with another
monitor, I found myself short on cash and physical desktop real
estate. I simply had to find a way to use a second monitor
with my mini. I came up with a few ideas: The KVM tangle was
overpriced, and no USB-to-SVGA solution yet exists for the Mac.
You can't tell me that Apple, a company that's thought of nearly
everything, forgot about a dual monitor solution for the mini!
As it turns out, OS X Macs have a Unix underlayer called Darwin.
Stemming from Unix, you can only guess how many thousands of
programs now run on Macs. Many of these programs and utilities have
been released under a BSD, GNU, or GPL license. This translates
into free use (for us non-developer, noncommercial,
non-profiteering types), and some of these programs are categorized
as freeware, shareware, or careware.
All of this starts with a free download (which discloses the
apropos license) and ends with a very stable and thoroughly
developed product. Without drowning in the politics, I'll refer you
to the Wikipedia and the
respective project pages for details on those licenses and their
uses.
To complete my project, I started with RealVNC (Virtual Network Computing).
It's simple to use, includes a server and viewer, runs on any
platform, and functions across platforms.
I then downloaded OSX2X, which runs
on my mini and is touted as an "excess keyboard remover". It
basically allows you to control a computer running VNC or X11
servers with one keyboard and mouse. Very handy.
The only thing I needed was another (cheap and readily
available) monitor for my PC and a crossover ethernet cable. I
scrounged for some parts to make a functioning, minimal
installation of Windows XP and set that computer next to my desk
with the monitor on a two-drawer file cabinet. I ran a crossover
ethernet cable to my mini, which was to act as a firewall, router,
and the brains behind this operation.
- Editor's note: If you already have an ethernet hub or switch,
there's no need for the crossover cable. Regular cables will do.
Also, if you're linking two Macs, you might try FireWire networking
for top speed. dk
Sharing the Internet connection is a breeze with OS X, and,
thanks to Samba (another Unix thing), sharing files is easier than
eating lettuce!
OSX2X is easily configured so you can run your mouse off one
edge of the monitor with the Mac desktop on it, and it appears
immediately on the corresponding edge of the monitor with the PC
desktop (or whatever your second computer is running) on it.
I use my Mac mini with one monitor and have a second monitor
hooked up to my old PC on the side - it looks and works like an
extended desktop with dual screens, even though each screen belongs
to a separate computer. I can even cut and paste between the two
platforms.
This turns out to be really useful for doing processor intensive
tasks that you don't want to have tie up your Mac. Say I wanted to
uncompress video or compress video. If I had the software to do
it on the PC, I could grab the file from the Mac, copy it over via
the crossover ethernet cable, and then set the PC to work - for
days if necessary - and still enjoy playing with my Mac.
I'm sure you'll find lots of useful things to do with this
setup, and I'd enjoy hearing all the great uses for it, too.
Remember, this will work across any platform. Two Macs, a Linux
box, and more. You can designate which direction the other monitor
is in, too, and OSX2X supports multiple connections. The one
drawback is that each computer needs its own display, but that may
cost you less than a KVM switch.
The only thing I regret is not hearing the birds chirp anymore,
as that old PC fan is still as loud as ever. Maybe if I smothered
it with this pillow.... 
Further Reading
Teleport is a freeware Mac-only solution that works with two or
more OS X Macs. We're currently using it with three G4 Power Macs
running Leopard and Tiger at Low End Mac headquarters. See 2 Macs, 2 Operating Systems,
1 Mouse, 1 Keyboard for more information on Teleport.
