Want to keep bacteria at bay? You could pop down to the pharmacy to buy some antiseptic soap, for example, but it might be easier to reach into your desk drawer. A roll of transparent adhesive tape can be turned into a nifty antibacterial film.
Depositing metal nanoparticles on a film surface can give it remarkable properties: silver turns it antibacterial, copper anti-fungal, and gold makes the film conduct electricity. What is tricky is getting the film to accept nanoparticles in the first place: in most cases you need a harsh chemical bath to break the bonds on its surface.