Easter egg (virtual)

A virtual Easter egg is a hidden message or feature in an object such as a movie, book, CD, DVD, or computer program. The term draws a parallel with the custom of the Easter egg hunt observed in western nations and many parts of Europe. The term is believed to originate in the movie Return of the Living Dead, where a military officer uses it as a code word for lost U.S. government containers of zombies created by a chemical spill.