QuarkXPress has a wonderful Alien Easter Egg:
(Requires: Quark XPress 4 or 6)

1. Have 1 box on the page selected.
2. Leave plenty of room on both sides for action.
3. Press Shift-Option-Command-K to get original alien.
4. Repeat above sequence at least 5 times.
5. The new alien appears randomly, usually after 5-12 tries.

Or another way to do the same thing:

1. Have at least 5 elements on page.
2. Have the Item tool selected in Tools palette.
3. Select 1 item
4. Hold down the Shift, Option and Command keys.
5. Hit Delete key
6. Watch out for alien!!!
7. Repeat steps 3 and 4.
8. When you get to the 5th item, something different happens.