Run Windows on Mac OS X with no reboot!“With its market cap at $213.9 billion, only two U.S. companies are bigger than Apple,” Philip Elmer-DeWitt reports for Fortune.

MacDailyNews Note: For a list of select companies’ market caps, please see: Apple shares hit new all-time intraday, closing highs – March 30, 2010

Elmer-DeWitt continues, “On March 9, a few days after the company announced the iPad’s ship date, Apple’s market capitalization (share price times shares outstanding) was $198.5 billion, making it one of the five most valuable U.S. companies, right below Wal-Mart and ahead of Berkshire Hathaway.”

“On Friday March 12, the day Apple began taking pre-orders for the iPad, its market cap hit $205.48 making it, briefly, the No. 3 U.S. company ahead of Wal-Mart — a position it held for just one trading day,” Elmer-DeWitt reports. “On Tuesday March 30, following a report that it was building an iPhone for Verizon, its stock rose 1.5% to $235.85, its market cap hit $213.9 billion, and it overtook Wal-Mart [$212.7 billion] once again to begin closing in on No. 2 Microsoft [$261 billion].”

Full article here.