Jeremy Bentham has been sitting in a corridor at University College London since 1850.
The moral philosopher, whose advocacy of animal welfare, prison reform, universal suffrage, and gay rights was far ahead of his time, left a will with specific instructions on the treatment of his corpse. In it, he decreed that his skeleton and mummified head be assembled, clad in a black suit and seated upright on a chair in a wooden cabinet, under a placard reading "Auto Icon." He also suggested that his corpse could preside over regular meetings of his utilitarian followers.
Bentham's plans for his remains became something of an obsession. For 10 years prior to his death, he reportedly carried a pair of glass eyes in his pocket so that embalmers could easily implant them into his head. Unfortunately, when the time came, something went wrong in the preservation process. Bentham's head took on a mottled, hollow-cheeked look, its leathery skin sagging under a pair of intensely blue glass eyes. Preservers created a wax head and screwed it onto the skeleton to ensure a more visually pleasing display, placing the real head between Bentham's feet.
The head sat undisturbed until 1975, when a group of mischievous students kidnapped it and demanded a £100 ransom be donated to charity. The university made a counter-offer of £10, and the students caved, returning Bentham's head to its rightful place. After a few more pranks, including one in which the skull was apparently used as a football, university administrators decided to remove the head from public display. It now sits in the Conservation Safe in the Institute of Archaeology and is removed only for special occasions.
Correction, Dec. 5, 2013: The headline for this post originally misstated that Jeremy Bentham died in 1850.