Hold Ctrl, Alt and Shift and don't release them. Go to Help, and select "About Program Manager...". Click twice on windows logo and press OK. Repeat this step and you'll get animated Windows flag and message. Repeating step again will show development credits and a image of Bill Gates, Steve Ballmer, other person or bear. Note: It's possible to do this easter egg on other programs.
Easter Egg Details: http://www.eeggs.com/items/469.html
Video demonstrating this easter egg:
ehatt493:
http://www.youtube.com/watch?v=zBYbJ1xGEiM
3:29 Before he shot to television fame, Ali G was a graphic artist on the Windows 3.1 team
fragglet 8 months ago