According to my personal feeling, the most impressive technique, developed in the last century is the overpainting of photographs.
This technique has the power to transform real places, real persons and real memories into something new and abstract. Just like in a dream, completely new situations are created out of bits of memories. In deed the whole context of the initial experiences is changed this way. And all the emotions related to these places and situations from the personal history can be overwritten by something new.
