This is a TV spot for the 1996 Chex Quest, which I think was the first time when a standalone mod of a popular game (Doom) was used to promote a product. It was distributed on a CD in more than six million of Chex cereal boxes, attracted a lot of fans, and apparently won an EFFIE for its effectiveness. I couldn't find the game on the list of winners on the official site, but one of its creators claims the game was responsible for a 248% lift in sales. The game was developed by Digital Café in Minneapolis, an early interactive agency co-founded in 1991 by Dean Hyers and Michael Koenigs. You can still download the game and its 2008 sequel here. If you'd rather watch than play, here's a five-minute speed run through the game.