Dynamic form field generation

I need to create survey forms that allow users to add and fill out as many of a particular field as necessary.

For example, I have users who need to enter information for each property that they own. Users all have varying numbers of properties. I would like to the user to start the form with one "Property" fill-in and then have a button below that which says something like "Add another property." When clicked, this button dynamically generates another property field on the page.

I know there is a some sort of "show/hide" functionality. But is there anything that's more genuinely dynamic?

Thanks!

- Mike