Irvine Kaye was an American businessman who created novel amusements from the 1960s until 1981, such as arcade games, luxury pool tables, and foosball games. A fan site devoted to his work describes an innovative pool table that was shaped like an ellipse and had a pocket off the center. Playing on the table requires thoughtful math work to calculate angles.
A few of Kaye's Ringo tables, as he named them, survive to this day. At 56 inches across, each unit sold for $225. Among Kaye's customers was the US Army, which purchased three for a hospital in Japan. As Ringo tables were smaller than standard pool tables, they were able to fit into the confines of therapy wards in hospital facilities.
-via Weird Universe