The University of Nebraska is greeting Omaha visitors with a familiar face -- the Oracle of Omaha, Warren Buffett, a 1951 graduate of the University of Nebraska, is featured in a series of ads that have been placed in the Omaha airport and on mobile billboards. The campaign was unveiled for the annual shareholders meeting of Berkshire Hathaway, which drew more than 30,000 visitors. The airport ads will continue through the summer, greeting visitors who come to Omaha for the College World Series and Olympic swim trials. The ads carry several messages including "What's A Good Education Worth?" and Buffett's long-standing advice to students, "Invest In Yourself."