1. A method for providing input to an application executing on a computer system having an interactive display surface, the method comprising the steps of: (a) executing the application on the computer system, the application having at least one attribute that can be adjusted during execution of the application; (b) determining a primary location adjacent to the interactive display surface where a primary physical object has been positioned by a user; (c) determining an additional location adjacent to the interactive display surface where an additional physical object has been positioned by a user; (d) associating the attribute with the primary location and the additional location; (e) determining a change in position of at least one of the primary location and the additional location; and (f) adjusting the attribute based on the change in position of at least one of the primary location and the additional location.