4. Game Genie
This is the granddaddy of all cheating devices. Literally it came first and set the standard for copycats to come for a long, long time. First released by Galoob in 1988 for the Nintendo Entertainment System, Game Genie let players do anything. By plugging your NES cartridge into the Game Genie first and then plugging the resulting hybrid into the console, gamers could enter in codes (looked up in an accompanying book) that changed different mechanics of the game. Depending on the game, Game Genie unlocked infinite lives or ammunition, invincibility, allowed players to begin a game with items acquired later, caused the player character to jump incredibly high, gave the gamer unlimited time in games with clocks, and much more. The device was actually protested by Nintendo on the grounds that the product created by it, a modified Nintendo game, violated copyright. Most cases like this are bunk, in my humble opinion; there isnt any way Game Genie took away from Nintendos profits because it only worked if you had a Nintendo game to plug it into in the first place. Thankfully, the courts agreed. Galoob survived and the Game Genie seemed poised to become a staple. Sequels followed for the Super Nintendo and Sega Genesis, delighting cheaters everywhere. Sadly, Game Genie hasn't been heard from since, but there are always rumblings of its resurrection.