Ancient Apple Easter Egg

Back in the mid '90s one of my Macintoshes had an easter egg, which I'm almost certain could only be accessed at boot time. You saw an image of the headquarters, a flag pole, and the flag was flapping in the breeze. You could control the direction of the wind by moving your mouse, and if you did it just right, you could rip the flag off the flagpole and then sail it to the ground. I think it was on the Quadra 840av. Can someone confirm this, or even better, post a screenshot? Thanks!