A LED-Throwie is a LED mounted on a coin cell battery in combination with some sort of a glueing material, such as a magnet for throwing it on metal. LED-Throwies were invented by the Graffiti Research Lab (GRL) aroung 2005, as a destruction free variant of a public lightning graphity. LED-Throwies are used mainly for street art or as light effects for events. There are no limitations for endless applications on public statues, buildings, bridges or transport.
Watch this cool project where artists have taken the concept and created indestructible waterproof lanterns, filled a hundred helium balloons and tethered them all together to create an etheral, floating sculpture, and connected them with Integrated Circuits that blink Morse code.