Super simple. Press any key (I actually prefer using the enter key) to roll an infinite-sided die to see if you can match the highest roll. I can do 13 KPPS (Key Presses Per Second). Comment how fast you can go in KPPS! (If you haven't noticed yet, at the bottom left corner, there is the KPPS statistic)
How it works: Every player has a "roll value". This increases every time you roll and thus increases your chance of getting the second or highest roll. When you click the green flag, it sets your roll value to the same value that the player who set the highest score had. When you beat the current highest roll by more than 500, you will receive a token that will allow you to upgrade something.