On Wednesday we learned that a new Chevy promotion is asking students to create their Super Bowl ad. This morning Promo Mag reports that Frito-Lay yesterday launched a similar contest to create a 30-second spot for Doritos to air during Super Bowl XLI. Frito-Lay, with help from Yahoo! Video who is hosting the contest, will narrow down the entries to 5 and then let the public vote on the brand's website in January.

"In today's increasingly reality-driven world, people are looking for new ways to interact with, help shape and even personalize what is important to them," said Doritos VP-Marketig Ann Mukherjee in a statement.

"While we've had great success with star-studded Super Bowl commercials in years past, today we are most inspired by the people who love Doritos chips; this year, they're telling us they want to be in control and we're giving them that control on one of the world's most watched events," she said.

Doritos' ad agency, San Francisco-based Goodby, Silverstein & Partners was instrumental in staging the campaign, from concept to Web site design (including the terse "creative brief" that gives entrants their marching orders) and judging. Was it hard for the agency to give up its chance to shoot a huge production number, as it has in years past? "They'll be doing plenty of work throughout the year for us," says Frito-Lay spokesperson Jared Doherty.