Here's a look at three types of urban light art: dorm room tetris, lightstick air animation and architectural projection bombing.

Light graffiti, also known as light painting, is a kind of leave-no-trace, sustainable and incredibly awesome temporary graffiti if captured right by clever photographers.

With tons of energy, some fresh ideas and a willingness to play around and be goofy, the photography duo MRI creates graceful portraits of light in motion.