Four displays. Three Computers. Two Operating Systems. One set mouse and keyboard. The mouse and keyboard control all three computers via a program called Synergy. The operating systems are Mac OS X Panther and Linux 2.6.8.1 (I’m having problems with 2.6.9, waiting for 2.6.10, so cut me some slack). The center computer with two displays is home-built, an Athlon 2800+ (what, only 32 bit?), while the laptop on the right is my lab workhorse, the 1.33 GHz 17″ AluBook, and on the left is my 500 MHz 15″ TiBook. They all have their own WiFi links to the house network, but the Synergy stuff is running over 100 Mbit/Full ethernet directly from the laptops to the desktop. My motherboard has two NICs built in, and the laptops have auto-crossover NICs in them, no need for crossover cables or switches/hubs/routers/etc. I’m very happy.

EDIT: My 500 GB external drive is mounted on the Linux box and shared over appletalk (on the Ethernet, not WiFi) along with my Linux home drive to both laptops, effectively giving me one working filesystem.