(Jeroen Bosch, Jerome Bosch)

Bosch used images of demons, half-human animals and machines to evoke fear and confusion to portray the evil of man. The works contain complex, highly original, imaginative, and dense use of symbolic figures and iconography, some of which was obscure even in his own time. He is said to have been an inspiration to the surrealism movement in the 20th century.

The Garden of Earthly Delights (triptych central panel, 1504, Museo del Prado, Madrid) http://en.wikipedia.org/wiki/The_Garden_of_Earthly_Delights

Bosch moved away from postcard-perfect images by applying rough layers of paint in a style that came to be called impasto. He left the drawings under his paintings visible, and this gives his work a very modern feel. Bosch also ~invented genre painting in the occident: he was (one of) the first painter to actually paint secular stories.

http://en.wikipedia.org/wiki/Hieronymus_Bosch
http://www.bbc.co.uk/bbcfour/documentaries/features/bosch.shtml
Figurines based on Bosch paintings!

Interesting article (!on a dodgy site!) about other renaissance oddities:
Story of Renaissance oddities – from Breast to Beard