Paints
One of the first commercial applications for nano was the use of carbon nanotubes in paints. An early success was 'barnacle busting' paints. Algae and barnacles couldn't cling to the nano paint on ships and tankers and were just washed away, saving lots of money on cleaning, huge fuel savings and replacing previous coatings which were dangerous to marine life.
Nano can give both coatings and paints improved qualities making them of increased hardness, scratch, mould and bacteria resistance, easy clean and so lasting much longer in between applications.
The paint used on the Forth Bridge is said to include nano components - but now, instead of needing to start painting the bridge again when they have just finished it, as the saying goes - the bridge won't need painting for 25 years!