[Undertoad]

According to Spluch, translating this Xinhua entry,

A man from Hunan Province of China can place glass balls, wooden poles and other objects on top of his rolling eyeballs without feeling any discomfort. Chen Xiang, a two Guinness World Record holder, can even perform Chinese calligraphy with his eye clamping a brush or even play the piano with his eyes! Writing words on his eyeballs with a brush also does not pose as a problem for him.

How does he do it?

Why is it that Chen Xiang's eyes not only can allow contact with foreign objects, but also bear tremendous weight? Doctors did an eye checkup on Chen Xiang and discovered that physically, his eyes are of no difference as compared to others. However, eye specialists pointed out that the sensory system for his eyes are much slower than normal ones. They even pointed out that his eyes should feel painful while making such performances, but as he is convinced that he has "supernatural powers", hence mentally he is able to control the discomfort.

Doctors have advised that he should not carry on with the performances, and infection may occur, which causes blindness.

Um yeah.