Stumbled across this link over at Make...basically, it's a cheap ($33) LVDS driver board for LCD panels. Seems to offer a pretty large list of compatible LCD panels, though I don't know off hand if any of them were used in the Mac models most people want to convert into an external monitor.
http://www.ebay.com/itm/Compatible-R-RM5251-LCD-Controller-Board-Kit-DVI-/270802804706
Holy Crap! That looks very promising.
That's pretty cool.
From what I interpreted from the auction text, the board comes with firmware for a specific LCD panel, to be flashed to your needs at purchase, and is not swappable with other panels without different firmware.
The same seller offers a programmer and lists firmwares available, but I note doesn't mention where to get these firmwares or whether you'll have to pay for them.
Reconditioned LCD monitors are so cheap now, this only seems practical if you can use it with good refresh rates on a larger monitor.
Noone would really care about some old LCD these days thats for sure.
But I think he is talking about turning those G4 iMacs into Intel "Macs" or something along those lines.