It better be something good. The best easter egg I've seen was on the Power Macs circa System 7.5 (if only I'd bought shares of AAPL instead of that Power Mac.

It better be something good. The best easter egg I've seen was on the Power Macs circa System 7.5 (if only I'd bought shares of AAPL instead of that Power Mac...) where you could type "secret about box", drag and drop it to the desktop, and get a full-screen animation (very impressive for the time) of an animated flag flying in front of One Infinite Loop. The mouse controlled the direction of the wind. The flag showed (for reasons which were no doubt hilarious to the folks who coded it in) an iguana with a power plug for its tail, and a banner below "Iguana Iguana Powersurgius".