Other terms used to refer to this phenomenon are "unofficial art" or "underground art."

The Lock On style is a "non destructive" form of underground art.

Running second to the subway system for underground art?

In 1995, he organised an international festival of underground art for which he received considerable critical acclaim.

A vibrant, underground arts scene has begun to emerge as a result.

Arthrob were an underground arts collective in London during the mid-late 1990s.

She has some 2,000, reportedly the largest collection of underground art in the United States.

The gesture was a token of the long-awaited recognition of underground art by the state.

Apart from some truly radical things being done with books, zines and the Internet, it is the nearest thing we have to an underground art.

He is a member of the underground art collective known as Fort Thunder.