jQuery Before/After Plugin

I was reading the New York Times online and they had an article which showed a road in Brooklyn that had been reconstructed to make it safer and more pleasing to the eye. To show the difference in the reconstruction project, they showed a before and after picture using Flash that let the visitor drag a slider over the images, which were sandwiched with one on top of the other, so that you could easily see how dramatic the changes were. I immediately thought that this could be done in JavaScript using jQuery, so I set out to do it.