The first popularly recognized easter egg can be found in Atari’s Adventure.Adventure, originally for the Atari 2600, was a very popular action adventure game that sold 1 million copies. This game proved to be 1st in many categories as it is recognized as the 1st action adventure game for a console, and was also the first game to allow a player to pocket, or stash items. A player could carry around several items at one time, and had the ability to choose a specific item using the keyboard or joystick without having to type in a command. These facts are nice and all, but the one thing people always remember is the birth of the easter egg in video gaming! (Easter egg: A hidden feature in a video game that is totally irrelevant to the advancement or completion of a game. An easter egg can be a picture, mini game, or anything else a programer feels inclined to add.)
Apparently, at the time, Atari did not think it necessary to credit designers for their work. So Warren Robinett, in protest, programmed in a hidden message crediting himself as the creator. The screen can be found,
“In the depths of the black castle in Games 2 and 3, which required special tools, direction, and a certain amount of know-how, players could maneuver to a room by the catacombs that had a single-pixel gray dot, the same color as the game's background. The dot would allow players access through a wall to a superfluous area with the text "Created by Warren Robinett" running down the middle.”
(The Greatest Easter Eggs in Gaming, GameSpot.com)
Robinett, I raise my controller to you out of respect for not only making video game history, but also for finding a geeked out way of "d@mning the man!!"