Copy and paste this into any cell in OpenOffice Calc and you can play Space Invaders in your office suite:
=Game(“StarWars”)
Wow! It’s true! Not quite like the original, though. If you try to paste it again it says “Oh no, not again!”
I remember having read in a billion places about similar things in MS Office (which by screenshots seems to be true, didn’t think it was…).
I ran into a few OpenOffice Easter Eggs at Wikipedia.