As with the previous version, generates a Unique URL each time Add button is clicked. This version has been further refactored to follow Mike Stenhouse's technique of periodically polling the URL, so you can do all the things you normally assume about URLs - cut-and-paste it, bookmark it, mail to a friend. Also you can hack the URL and watch the display update.
Fill in as many fields as you like, then "Add" to add them up.