The photograph Monologic - Yo-Yo 1, 2 (U.F.O.),(1982), shows Koller playing with a big white Yo-Yo in a drab concrete building among a group of tower blocks. For him, games like ping-pong or the yo-yo representsed the possibility of a more playful society in the face of socialist standardization.
Koller's semiological manipulations of landscape and topography, of places and (his own) faces, investigate the possibilities of shifting meaning by the simplest alterations. In deadpan-humorist fashion, most poignantly displayed in a series of photo-portraits that cover a period of more than four decades, he systematically explores the relationship between art and alienation, or the idea of art as alienation. "U.F.O.-naut J.K." becomes the artist's altered ego, an extraterrestrial maker and distributor of universal signs: question marks, Ping-Pong balls, or wave lines, a more recent signature symbol, formed by tennis balls in a swimming pool in 1992 or drawn on the floor in the "antiperformance" Nova vaznost', 1991." (Tom Holert, Artforum, October, 2004).