Apple's stock market value topped the $500 billion mark in pre-market trading Wednesday, another record high for what was already the world's most valuable company.
The half-trillion dollar valuation puts Apple in some extremely exclusive territory, making it one of the five most-valuable companies at any point in history. Only Microsoft, ExxonMobil, Cisco (CSCO, Fortune 500) and General Electric (GE, Fortune 500) have ever surpassed that mark.
Exxon did it most recently in late 2007, when oil prices were soaring. Microsoft, Cisco and GE reached half a trillion dollars in market capitalization in 1999 during the height of the tech bubble.
Microsoft was the only company ever to have a valuation of $600 billion. Its market cap now sits about $267 billion.
Apple's valuation is now higher than the gross domestic product of Poland, Belgium, Sweden, Saudi Arabia, or Taiwan. (For more comparisons, check out this excellent blog: Things Apple is Worth More Than.)