Magento. Is it possible to have a product that is either physical or downloadable based on a drop down?

I have an online music store based on Magento/Zend. We’re currently adding downloadable mp3 versions of the albums that we sell.

We’d like it so that the customer can select either physical or downloadable from a drop down on the product page when buying rather than have two separate products?

Is this possible within the default Magento configuration of w开发者_运维百科ill have to extend Magento to get this functionality?

I don't think there is any default feature but might be achieved by custom work. Would you keep the downloadable file free or paid. I had an idea to create custom options and create some checks that allow.

The downloadable link and ask no shipping charges.

Or

Charge shipping charges too and don't allow downloadable link.

Based on the custom option selected.