Dwight Goldthorpe ($23 million)

A private investor, Goldthorpe left most of his fortune to his alma mater, Amherst College, where he graduated in 1941. Goldthorpe died last year at 87 in Palm Beach, Fla., where he had been retired for decades after quietly amassing millions though independent investing. He asked that his bequest, the largest in Amherst's history, be used to enhance the liberal arts school's buildings.