Adolf Wölfli (1864 – 1930) was a visionary artist from Bern, Switzerland. Here's a video compilation of his brilliantly intriciate drawings. I never tire of looking at his work. His drawings are mandala-esque, containing many images within images. Wölfli was one of the first people to be recognized as an "outsider artist". He spent a large portion of his life inside of a psychiatric hospital, where he made his drawings.
"At some point after his admission Wölfli began to draw. His first surviving works (a series of 50 pencil drawings) are dated from between 1904 and 1906." Every Monday morning Wölfli is given a new pencil and two large sheets of unprinted newsprint. The pencil is used up in two days; then he has to make do with the stubs he has saved or with whatever he can beg off someone else. He often writes with pieces only five to seven millimetres long and even with the broken-off points of lead, which he handles deftly, holding them between his fingernails. He carefully collects packing paper and any other paper he can get from the guards and patients in his area; otherwise he would run out of paper before the next Sunday night. At Christmas the house gives him a box of coloured pencils, which lasts him two or three weeks at the most (Wikipedia)."
From youtube: At the beginning of the twentieth century, Adolf Wölfli, a former farmhand and laborer, produced a monumental, 25,000-page illustrated narrative in Waldau, a mental asylum near Bern, Switzerland. Through a complex web of texts, drawings, collages and musical compositions, Wölfli constructed a new history of his childhood and a glorious future with its own personal mythology. The French Surrealist André Breton described his work as "one of the three or four most important oeuvres of the twentieth century."