This billboard was in the corner of a parking lot that ran between Shipley and Folsom, and faced the oncoming Folsom traffic. They regularly were defaced, but this "ART FOR AIDS" one was particularly galling, what with Chevron et al glomming onto publicity without really doing anything "about AIDS" (tm).
The detournment reads "Mercenary
SELF promotion" and "(Chevron) YOU STILL SUCK!". The dazzling being
from an alternate plane of existence appeared, visible here in the
lower left corner, transfixed by the profound detourn and breathtaking
art. Either that or it's a blob on the print.