Building a Cockpit Setup for Simulator Games?

Milo_Mindbender asks: "For awhile I've been looking at building a cockpit-like setup for playing simulation games. One problem is finding a way to hook up a large number (up to 100) of lighted push-buttons in the thing and interface them to a computer that would poll the switches and control the (Tri-color LED) lights. Since the buttons/LEDs won't be clustered together, it would be nice if each button (or group of 4-5 buttons) could be on some kind of multi-drop network so the thing wouldn't turn into a wiring nightmare. The trick is that you don't want to miss button presses and you want to let people hold down multiple buttons without the setup getting confused. The big problem though, is cost. Anybody got an idea of how this could be done, preferablly with off-the-shelf parts, for under $5-$10 per button including the button?" Combine this idea with the earlier article we did on LCD-screens-for-cockpits, and you might have a kick-ass setup! Networked mech sims, anyone?