Szkieletor (Skeletor) is the unofficial name of a 92 metre high-rise building in Kraków, Poland, originally intended to become the headquarters of the Main Technical Organization (Naczelna Organizacja Techniczna). The construction of the building was started in 1975, but was stopped in 1981 because of economic constraints. Due to the unfinished building's resemblance to a skeleton, it was nicknamed after Skeletor, the arch-villain in He-Man and the Masters of the Universe, a cartoon which was popular in Poland at that time.
In recent years, several investors have been interested in the building but have been discouraged by the complicated legal status of the land on which it stands, as well as the high cost of its demolition or adaptation.
It is located near the Mogilskie Roundabout (Rondo Mogilskie) and Cracow University of Economics. Defining the "tallest" building as not including antennas (the most standard definition) it is the tallest building in Krakow. Currently this building is being used to host billboards for advertising purposes.