This is not a game.
As an effort to stave off madness and superstition, it constitutes a rather simple widget which enables one to estimate, by naive application of Bayesian inference, how likely it is that event X causes is the cause of an effect Y, given that you had some initial estimates, and are able to test it.
Windows Program [8MB; apologies]
OSX 10.4+ Dashboard Widget [125KB]
iPhone web app [only works on iPhones and in Safari]
Sources to the above [174K. Includes an additional PyQt4 version not linked to above]