Microsoft co-founder Bill Gates wishes he wasn't the world's richest man, he said last week.

"I wish I wasn't," he said during an online advertising conference last week. "There is nothing good that comes out of it," he added.

Worth an estimated $50 billion, Gates and his wife support the Bill and Melinda Gates Foundation, a philanthropic organisation that manages $29.1 billion of funds to support worth causes.

Gates admitted that he doesn't get hassled too much when he's out in public, bar being asked for an occasional autograph.

He also said he has no political ambitions: "I wouldn't like it, I wouldn't be elected," he said.