In 1980, a moving image installation called the Masstransiscope was installed in the abandoned Myrtle Avenue subway station in Brooklyn. Since then it's been seen by millions of commuters for over 30 years. The piece, made of 228 hand-painted panels courtesy of artist Bill Brand, was based on the principle of the Zoetrope, a 19th century optical toy. When you pass by it in the subway (which you can do on the Manhattan-bound B and Q trains, just past the DeKalb Avenue stop) it resembles a moving picture. We revisited the piece in 2008 when it was restored, which just happened again this year—here's Brand discussing the latest restoration:

And here's what a great collection of news clips showing what straphangers thought about it when it debuted in 1980:

[h/t Untapped]