throttling function

	function throttle(f, delay){
		var timer = null;
		return function(){
			var context = this, args = arguments;
			clearTimeout(timer);
			timer = window.setTimeout(function(){
					f.apply(context, args);
				},
				delay || 500);
		};
	}

Use in functions like keyup to throttle the rest of the function from runniing

.keyup( throttle( function() { /* your function here */ })