cyanotype is one of my favourite media. 

it combines handprinting with modern photography and even in edition printing each print has unique aspects, depending on the compound of the chemicals, different paper, coat of paint and mainly the exposure. 

i mostly use the sun for natural uv-rays, but also with special uv-lamps the results are never completely predictable. by combining the traditional use of this technique, which is printing with plants, and modern ways with negative images this technique shows nearly infinite possibilities.