Well after Columbia's application deadline, Buffett wrote to Professor David L. Dodd:
“Dear Professor Dodd, I thought you were dead, but now that I know that you’re alive, I’d like to come study with you,” Mr. Buffett said he wrote in his letter.
“And he admitted me to Columbia!” Mr. Buffett said. “I would not be who I am today without David Dodd. If in response to my letter he’d said, ‘Sorry, its too late,’ I’d never be where I am.”
“Harvard did me a big favor by turning me down,” he said. “But I haven’t made any contributions to them in thanks for that.” 
Also, Warren Buffett doesn't think he pays enough taxes.... well go on then, pay some more.