This game has hidden developer credits.
Millionaire is basically Monopoly with its locations changed to places around the world and casino games tacked on. At least there's no Mahjong.
Hidden Copyright Info
On Player 1's turn, press Up, Start, Left, Select, Down, Select, Right, Start, Select, Select, Start to show a slightly extended version of the copyright info on the title screen. This code only works if Player 1's type is set to one of the Joysticks.