In case you weren't aware, the Dallas Cowboys are essentially printing money.For the third straight year, America's Team tops Forbes' list of the world's most valuable sports franchises. The Cowboys' value comes out to $4.8 billion, according to the list, with Forbes noting they have the highest revenue ($840 million) and earnings before interest, taxes, depreciation and amortization ($350 million) of any franchise.The nearest competition is Manchester United at $4.123 billion.