The prizes, in many cases: funds to help turn it into an actual business.

USC senior Nick Smith's team entered an idea for a small sail that could be used by skateboarders and skiers.

"We want to use the money to explore a more abrasion-resistant fabric for a pro model," said Smith, 22, whose Sporting-Sails start-up was one of the three entries to win a $12,500 top prize this month at a schoolwide competition for new venture ideas.

The nylon sail is designed to help extreme skateboarders and skiers slow their descents and increase their maneuverability. A version of the product is already sold online, but the business needs funding to buy fabric for a new version, Smith said.

The contests are "an extremely safe-haven environment for students to get a real glimmer of what it's going to take to start and launch a business," said Bryce Benjamin, chief executive in residence at the Lloyd Greif Center for Entrepreneurial Studies at USC's Marshall School of Business.

The Marshall School is working on a contest aimed at digital media applications, with $50,000 to $100,000 in prize money, Benjamin said. And the new Annenberg Innovation Lab at USC's Annenberg School for Communication & Journalism is hosting new-media design competitions with $25,000 in prize money.

Also at USC, the Viterbi School of Engineering will host a contest with about $50,000 in prizes.

Even those who don't win get something valuable: feedback from the investors who serve as judges. And everyone gets to network.

"We made a lot of connections, although, honestly, over the past week we made so many I can't remember them all," said Justin Lewis, 21, a senior at USC. He was part of another team that won a top prize at the recent USC competition. The idea: PlayOnSocial, which would let users log in to online games and websites through their existing social-network accounts.

Rice University in Houston has one of the biggest business-plan competitions. It's intercollegiate, and this year it got more than 420 applications, vying to compete for a share of $1 million in prizes. In 2001 the prizes totaled only $10,000.