Incorporating nanoparticles in paints improves their performance by making them lighter and gives them different properties. This is because thinner paint coatings used for example on aircraft would reduce their weight, save fuel and beneficial to the environment within the life cycle of the aircraft. It is also be possible to substantially reduce solvent content of paints, with resulting environmental benefits. New types of fouling resistant marine paint could be developed which is urgently needed as alternatives to tributyl tin (TBT) in view of the ecological impacts of TBT. Anti-fouling surface treatment is also valuable in process applications such as heat exchanger, where it could lead to energy savings. If they can be produced at sufficiently low cost, fouling-resistant coatings could be used in routine duties such as piping for domestic and industrial water systems. It remains a speculation whether very effective anti-fouling coatings could reduce the use of biocides, including chlorine. Other novel, and more long-term applications for nanoparticles lie in paints that change colour in response to change in temperature or chemical environment, or paints that have reduced infra-red absorptivity and reduce heat loss.