10 January 2000: AOL and Time Warner announce a megamerger

America Online agreed to acquire Time Warner in a stock deal valued at roughly $165 billion, the biggest merger ever at the time. The pitch was old media meets new media. In reality AOL was using an inflated dot-com share price to buy real assets. The combined company later reported a loss of nearly $99 billion for 2002 after writing down goodwill. Synergy, it turned out, was mostly a press release word.

The lesson: Paying with overvalued stock is clever for the buyer and a disaster for whoever accepts it.