Abstract: In one general aspect there is provided a method for distributing software. The method comprising (a) a software user creating a user profile which includes one or more types of biometric data; (b) providing the biometric data to a software distributor; (c) obtaining the software; and (d) utilizing the software on the user's computer having a biometric sensing device that senses or measures a biometric parameter of the user useful for creating biometric data, wherein utilizing the software causes the activation of a verification program or function that compares the sensed or measured biometric data to the biometric data in the user profile. In another aspect, the invention relates to a method of handicapping two or more players of a game of skill, wherein the players are of varying skill levels. Also provided are methods of ranking players according to skill level and generating a professional gaming league based on skill level.