I also only use them when I absolutely need to, but this time its more for looks than functionality. In both FF and IE, the website works fine, but in IE 7 there is a slight rendering difference. The links on the left side appear to have more padding in IE7 than they do in Firefox. Take a look: http://www.barkleigh.com/
I could adjust the padding for IE7 by using the hack to make it look more like the Firefox rendering.