Webform Quantity Total

When a 'Quantity total' field is added to a webform, admin's enter a per unit price in the admin ui.
When the webform is to be filled out by a user, a textfield called Quantity is displayed. The user enters a quantity, a jQuery functions multiplies the number by the per unit price (entered by the admin) and displays the total.
A page total field is also available that calculates sub-totals.