Simple jQuery plugin to emulate position: sticky

jQuery.scrollSticky

/******************************************************************************
* jQuery.fn.scrollSticky
* Applies a UI state class to an element when the user scrolls to it. Works well
* for fixed positioning UI that is dependent on scroll
*******************************************************************************/
$.fn.scrollSticky = function ( options ) {
	var methods = {
		init: function() {
			return this.each(function ( index ) {
				var $item = $( this ),
				    offset = $item.offset().top,
				    time = new Date().getTime(),
				    id = time + index;
				
				// if item is already sticky, exit
				if ( $item.data('isSticky') === true ) {
					return false;
				}
				
				// set data id as namespace so event can be unbound	without affecting other sticky events
				$item
					.removeData('sticky-id')
					.data('sticky-id', id)
					.data('isSticky', true);
				
				// bind custom scroll event to window
				$(window).bind('scroll.stickyscroll-' + id, function() {
					var docScroll = $(document).scrollTop();

					if ( docScroll >= offset ) {
						$item.addClass('s-fixed');
					} else {
						$item.removeClass('s-fixed');
					}
				});
			});
		},

		reset: function () {
			return this.each(function () {
				var $item = $(this),
				    id = $item.data('sticky-id');

				// if sticky id is false, exit
				if ( !id ) {
					return false;
				}
				
				// unbind custom scroll event
				$(window).unbind('scroll.stickyscroll-' + id);

				// remove sticky attributes
				$item
					.removeData('sticky-id')
					.removeData('isSticky')
					.removeClass('s-fixed');
			});
		}
	};
	
	// if options is a valid method, execute it
	if ( methods[options] ) {
		return methods[options].apply( this, Array.prototype.slice.call(arguments, 1) );
	}
	// or, if options is a config object, or no options are passed, init
	else if ( typeof options === 'object' || !options ) {
		return methods.init.apply( this, arguments );
	}
};