setTall = function() {
	if (document.getElementById) { // Do you know the DOM?
			var divs = 	new Array(	document.getElementById('leftContainer'),
									document.getElementById('rightContainer')
			);

			var maxHeight = 0;

			for (var i = 0; i < divs.length; i++) { // Get the height of the tallest column
				if (divs[i].offsetHeight > maxHeight) {
					maxHeight = divs[i].offsetHeight;
				}
			}

			maxHeightRightColumn = 0;

			topRightHeight = document.getElementById('topRight').offsetHeight;
			bottomRightHeight = document.getElementById('bottomRight').offsetHeight;

			maxHeightRightColumn = topRightHeight + bottomRightHeight;


			if (maxHeightRightColumn > maxHeight) {
				maxHeight = maxHeightRightColumn;
			}

			for (var i = 0; i < divs.length; i++) { // set the height of the tallest column
				divs[i].style.height = maxHeight + 'px';
			}
	}
}

addLoadEvent(setTall);