One way to ensure one column is the same height as another. Extra complex because I am using 'sliding doors' drop shadow on the columns. Appears to work in FF, IE, Opera, Chrome and Webkit but ymmv.

equal_height_columns.js

                  /**
                   * Equal height column hack for Favorites box
                   */
                  var fudgeAmt = (document.all === null ? 47 : 27);
                  var heightToMatch = $('equalHeightColumnsHack').clientHeight - fudgeAmt;
                  var shadowHeight = heightToMatch + 24;
                  var elems = {};
                  elems.container = $$('#featured .content')[0];
                  elems.shadow = $$('#featured .content .dropShadowHack')[0];
                  /* Prettified the getComputedStyle wrapper a bit over what's in the repo, see http://www.quirksmode.org/dom/getstyles.html */
                  var shadowBgLeft = (function(){
                    if (elems.shadow.currentStyle) {
                      var sty = elems.shadow.currentStyle;
                      return sty.backgroundPositionX;
                    } else {
                      var sty = document.defaultView.getComputedStyle(elems.shadow, '');
                      return sty.backgroundPosition.split(' ')[0];
                    }
                  })();
                  elems.container.style.height = heightToMatch + 'px';
                  elems.shadow.style.height = shadowHeight + 'px';
                  elems.shadow.style.backgroundPosition = shadowBgLeft + ' bottom';