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.