PokerStars 'World Championship of Online Poker' is just getting bigger and bigger every year since it started 7 years ago. In this years WCOOP not less than $40,000,000 is guaranteed in 45 events. Not many poker sites in the world other than PokerStars could guarantee these enormous amounts of money within the short time that WCOOP has been running.
Neither the PGA Tour or the ATP-tours biggest tournament 'Wimbledon' comes even close those to these kinds of prize pools. Since the first WCOOP was played, the total prize pool has grown with around 6000%, and probably it will continue increase in future WCOOP tournaments.