gleaned from online sources, would prefer a first hand verification-
Action Max -- 9V DC 500Ma Positive Tip or 4 C Batteries
Leisure-Vision -- 12V DC 500Ma Positive Tip
JVC x-eye --9.5V DC 1.5A Positive Tip
TurboGrafx-16 + CD Unit -- 11V DC 1.53A Negative Tip
Gameboy -- 6V DC Negative Tip
Game Boy Color -- 3V DC 300Ma
Nintendo Gamecube -- 12 V DC 3.25A Nonstandard Connector
Sega CD II -- 9V DC 1.2A Negative Tip
Sega Channel -- 15V DC 400Ma Positive Tip
Sega Pico -- 10V DC 0.85A Positive Tip
Supervision -- 6V DC 350mA
saturn, dreamcast playstation 1- indications are that all 3 cords are interchangable as the power conversion is done inside the console, hence no brick. however i have noticed that all saturn cords are rounded in the same way.
all of this info was cut n' pasted from
http://www.geocities.com/cpepin1976/voltages.txt
if you have any of this hardware on hand, take a second to double check it.