(function( $ ){
var methods = {
    init: function() {
        $(this).scroll(function(evt) {
            $(evt.target).data('options', Math.random());
            console.log($(evt.target).data('options'));
        });
    },
    get: function() {
        return $(this).data('options');
    }
};

$.fn.myPlugin = function(method) {
    return this.each(function() {
        if ( methods[method] ) {
            return methods[method].apply( this, Array.prototype.slice.call( arguments, 1 ));
        }
        else if ( typeof method === 'object' || ! method )
            return methods.init.apply( this, arguments );
        else
            $.error( 'Method ' +  method + ' is not declared for jQuery.myPlugin' );
    })
};
})(jQuery);

$(document).myPlugin();

var data = $(document).myPlugin('get');