1. A method for saving data from an applet to a local file system, comprising: downloading an applet from a server computer system to a client computer system; executing the applet at the client computer system, the executing producing a current applet state defined by a set of data; opening a browser window at the client computer system, the opening of the browser window being directed by the applet; providing a universal resource locator (URL) to the browser window, the URL being provided to the browser window by the applet, the URL referencing a script located on the server computer system, the URL providing the set of data to the script; executing the script located on the server computer system, the script execution being initiated by the URL referencing the script; sending the set of data from the server computer system to the browser window at the client computer system, the sending of the set of data being performed by the script; and displaying a dialog within the browser window at the client computer system, the dialog directing a user to select a location on a local file system of the client computer system for saving the set of data that defines the current applet state.