Outlook Easter Egg - Flying Sticky Note

Create a new sticky note (File | New | Note or Ctrl+Shift+N will do the trick.)

Type some text in the note (anything will do, it doesn't have to be long.)

Drag the note around the screen for a while (you can move it via the title bar just like a normal window.)

Now, for the big trick: Press CTRL+Z.

Sit back and enjoy the show.

You can keep pressing CTRL+Z again and again to reverse the process.