This 23-year-old Chinese ‘Rain Man’ Chou Wei has IQ 46, dropped out from Primary school at age 12 because his teachers and classmates discriminated him as an idiot.
This video shows he can mentally do very complex math calculations:
The full video (in Chinese):
https://www.youtube.com/watch?v=yHdrYo_N1x8&feature=youtube_gdata_player
Mathtuition88 