This is also the nom de guerre of Beijing graffiti artist Zhang Dali.

His signature piece - the simple spray painted outline of a head seen in profile - appears all over Beijing and is cropping up in other major Chinese cities as well.

Typically Zhang chooses one of Beijing's many older buildings marked for demolition in the cities' frenetic drive for modernisation. Perhaps the head represents an attempt to factor the human into the depersonalised process of urban renewal.

Interviewed in local entertainment magazine City Scene Zhang had the following to say about his art, which he describes as part of an ongoing work called Dialogue:

"I've made thousands of them in Beijing since 1995. The series is a dialogue between me, the people, and the changing environment of the city."

He sees his work as a protest against the 'here today, gone tomorrow' nature of Beijing's urban reconstruction which is destroying the cities' traditional low-rise sprawl of back-alley warrens and replacing it with tower blocks. These hutongs have long been seen as characteristic of and synonymous with Beijing. Zhang says:

"Real modernisation is in the mind. New York, Rome, Paris and Hong Kong - these are modern and beautiful, with lots of small old houses. And the people living in these homes are modern."

Zhang, 38 this year, is a native of the northern city Harbin. He studied at Beijing's prestigious Central Academy of Art and Design. As well as his graffiti, he is also a performance artist and sculptor. He says his education is one of the reasons the authorities appear to have turned a blind eye to his defacement of the cities' walls. That and the discovery "that I wasn't part of some underground society."

His more formal work has its widest audience overseas. A photograph he took was used as the front cover for the January 2000 issue of Newsweek. But it is in his adopted home of Beijing that his work is omnipresent and familiar to all who have spent even a short time in the city, where it has come to sound a small note of disquiet as the Tartar Capital of the Celestial Empire rushes headlong to embrace a concrete and plexiglass vision of modernity.