This example uses Yahoo! UI version 0.10 of yahoo.js, dom.js, event.js and dragdrop.js. I have created five JavaScript files called extend.js, dragdrop-override.js, dragdrop-override-2.js, apple.js and basket.js. The apple.js and basket.js files are the ones to look at closely. Download the zipped file of this example.
My blog entry about this example.