The term “Easter egg” is used metaphorically to refer to a hidden message, joke or feature incorporated into a movie, computer program or other media entity for users to stumble across and appreciate.
There’s something at once ironic and appropriate about this term in connection with a Google Easter egg — a sort of “Good Friday Easter egg” — I came upon some time ago when I happened to Google the words “God died.” Google’s own results feature proposed the following identifying information for this search:
Pretty cool, huh? Alas, this “Good Friday Easter egg” is now apparently defunct. (Please bring it back, Google people!)