Submitter here: For those who are not familiar with e-sport, Valve is holding The International 4, which is the biggest Dota tournament. The tournament begin with Valve's $1,600,000 base prize pool and Valve sells Compendium for $9.99. Each purchase contributes $2.50 to the prize pool. This thing begins on May. 9 and in 10 days, which is 2 months before the actual tournament, Dota players have contributed $4,028,459 as of now.