If you've noticed the ghost remains of bricked up windows, stairways that lead to sealed over doors, bridges and walls that were only partially built, you've detected Thomassons.
Akasegawa Genpei coined the term 'hyperart' to describe urban objects and structures that had grown defunct and useless over time, but for reasons of economy or lack of concern were never removed or destroyed. Instead, they became part of the landscape and maintained accordingly. Akasegawa specifically named the odd items, "Thomassons" after American League outfielder Gary Thomasson, who signed with the Japanese baseball team, the Yomiuri Giants. Although he was highly paid, he performed poorly, nearly setting a record for strikeouts.
Once useful, but now extinct.
Akasegawa wrote a magazine column, regularly describing the Thomassons he discovered and developed a following with readers who also sent in photos of curious, futile objects. The collection of columns and photos were published as a book, released in Japan.