I just read a joystiq article about how Digital Press is offering money for the discovery of easter eggs in certain games and after reading through what they're looking for it seems like a bunch of them could be possibly cracked by using TAS tools such as memory watch.
Digital Press wrote:
RAIDERS OF THE LOST ARK
● According to an interview with programmer Howard Scott Warshaw (in the Winter 1999 issue of Classic Gamer Magazine) a Yar will fly up through the treasure room (inside a mesa) when you start digging. It depends on the right configuration of (three?) items in your inventory. Chances are the flying Yar doesn’t exist, but is it possible that “something” happens with the right inventory?