It's supposed to be an almost unnoticeable reference to a pretty well-known person or thing, usually for laughs. Designed to please mostly everyone, when they finally notice.A hidden feature in computer software, a DVD, or a video game.
(And what the heck is up with demanding to get an easter egg named after you? Seriously people, I thought you liked contributing to the game for a hobby. Credit-free, I mean. Because ya know, it's fun? That's just my opinion 'though I guess.)