Burger King: Subservient Chicken-submissive chicken
While not the first "interactive" website, the Burger King promotion definitely exceeded all expectations when it went viral.
(Also see the blog post: "Influential interactive website designs: 10 of the best." )
Todd Fluhr is a freelance writer and multimedia designer. A self-described "Shockwave Rider" of technology, culture, and creativity, he has been involved in the interactive entertainment industry since the early 90's. He hopes to find time to sleep some day.