It would be a great option to have the ability to created calculated fields when building forms.  Basically, it would include selecting 1 (or more) fields within a form to create a sum, difference, quotient, or product between multiple fields as well as manually enter numbers to perform these calculations.

An example would be if I create 10 questions that require a number rating for each.  At the end, I would like to have a total number that can calculate automatically from each rating field.