Make some boxes on a website the same height. Add a common class name to the boxes, and swap out your class name for ".class-name-of-box". Requires jQuery.

gistfile1.txt

<script>
	function equalHeight(group) {
		var tallest = 0;
		group.each(function() {
			var thisHeight = $(this).height();
			if(thisHeight > tallest) {
				tallest = thisHeight;
			}
		});
		group.height(tallest);
	}

	$(document).ready(function() {
		equalHeight($(".class-name-of-box"));
	});
</script>