This entire website is built off the concept of rock, paper, scissors, lizard, Spock from season 2, episode 8 of The Big Bang Theory. It has the basic rules of rock, paper, scissors along with rules for new elements lizard and Spock. Along with these rules, there's added functionality to add your own elements to the game.
New elements could be anything you want to play around with, don't forget to add interactions though, or else the new element will be useless.
When adding new interactions, add them in the form of "x beats y". So if you were to, as an example, add a pen you could enter "pen beats paper".