Hanzawa released a 'Walkie Game' series of games (I'm guessing they mean the games are shaped sort of like walkie-talkies, handheld two-way radios). These games are flat, run on AA batteries (keeps them smaller), and even came with carrying straps so you could sling the game over your shoulder. So far I've seen Cosmic Twinvader, Grand Prix Turbo and Pack'n Maze released by Actronics, and Grand Prix Turbo released by Ludotronic. It's possible that the much more rare games Dig N Picman and Wanted G-Man were released in this style, but I haven't seen them yet. This is the same game as Challenge Racer and Bazin Racingcar Turbo.
(Click on thumbnails to enlarge)
