Gnome Easter Egg - The fish's water needs changing

1. Change your system date to April 1st of any year
2. Add the Fish applet to your panel (right click on an empty area, choose "Add to Panel...", then choose "Fish" from the list and click "Add")
3. The fish will appear upside down in a waterless box
4. Click it to see a "The water needs changing - Look at today's date!" message