Sega Action Chair
From Sega Retro
The Sega Action Chair is an extremely rare peripheral built for the Sega Mega Drive. It essentially combines the features of a Sega Mega Drive controller with a movable chair. The d-pad movements are mapped to the chair itself, so if the user leans left the on-screen character will move left too. As it uses a DE-9 port it is also compatible with Sega Master System games. It was initially released in 1992.
Action Chairs only appear once in a blue moon. The latest spotting was in May-June 2010 on eBay, with a buy-it-now price of US$500.