Phil Gordon, ex-host of Celebrity Poker Showdown on Bravo, is largely responsible for getting the Roshambo (i.e., Rock-Paper-Scissors) side event put in the WSOP a few years back.
Until very recently, a group of Phil's friends used to hold an informal event called the World Roshambo Championships in Las Vegas every year - $100 entry fee, winner take all (participants would get into a March Madness style tourney bracket, with a race to 10 for each "game"). That event has kind of morphed into the $200 entry World Series of Roshambo. (If I recall correctly, at least some, if not all, of the proceeds of the WSOR go to the Cancer Research and Prevention Foundation.)
Having participated in at least 5 of the informal WRCs in Las Vegas (and winning the championship one year), trust me, it's not child's play. There is a heavy dose of skill in reading the other person's tendencies and manipulating them into going what you want them to go - there is probably more psychology in Roshambo than any sport or game I have ever participated in. I personally witnessed one guy lose $10,000 in a night to another guy playing good ol' Rock-Paper-Scissors.
(There is another group that has been holding a "World RPS Championships" for probably close to 10 years now with a slightly different format - $25 entry fee, similar tourney style, first one to win 2 games of 2 out of 3). That group is not affiliated with the WSOR.)
