Harry Khane, the ultimate multitasker.

Via the excellent Proceedings of the Athanasius Kircher Society:

Harry Kahne, a hero of the Athanasius Kircher Society, was an extraordinary human being. In the picture above, he is writing with both hands, both feet, and his mouth simultaneously. The right hand is writing backwards and in reverse, and the mouth is writing backwards but correctly. Just one of his many extraordinary multitasking feats.
Rex Research has republished online “The Man with the Multiple Mind: An Interview with Harry Kahne, Whose Brain can do Six Things at the Same Time,” a 1925 article from Strand Magazine, as well as Kahne’s “Multiple Mentality Course,” his “true course in right/left brain training.”
Kahne is also described in Ricky Jay’s Learned Pigs and Fireproof Women.

The interview is an excellent read.