Aluminum to prevent Iron corrosion
Aluminum, just like zinc, is already widely used to coat iron surfaces to prevent corrosion (in the elemental form, or in combination with other metals, like zinc). You can deposit aluminum on practically any surface (including plastics). On metals it is done by electrochemical deposition.

There are several companies working with this type of coating nowadays, including AlumiPlate (http://www.alumiplate.com/).