In his eight years as CEO, Palmisano has spent more than $20 billion buying scores of companies to transform the mainframe maker into the world's leading provider of computer services and analytics software. With his stock at an all-time high, Palmisano intends to keep his wallet open: In May he said he'd commit an additional $20 billion to acquisitions over the next five years. He's also kept up IBM's habit of combining games with brains. This year IBM unveiled a computer that can beat a human at Jeopardy, an unbelievable programming challenge.
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