Apple's stock rose to another record high earlier today, reaching $228.36 at market close. That's almost another $10 above the record high it set back on March 5, which translates into nearly nine billion dollars in market capitalization gained in less than three weeks.
Apple's market cap is so high that only three publicly-traded US companies have market caps higher than Apple's: Exxon, Microsoft, and a little retailer called Wal-Mart. Apple will probably never catch up to Exxon's market cap, which exceeds Apple's by more than $100 billion, and it has another $55 billion to go before it can surpass Microsoft -- not likely, but not impossible. Apple's market cap is within striking distance of Wal-Mart's, however, with only about $5.5 billion more to go before Apple surpasses the market value of the world's largest retailer.