It was like holding the future in your little 10 year old hands.

https://en.wikipedia.org/wiki/Mattel_Auto_Race

Mattel Electronics Auto Race was released in 1976 by Mattel Electronics as the first handheld electronic game to use only solid-state electronics; it has no mechanical elements except the controls and on/off switch. Using hardware designed for calculators and powered by a nine-volt battery, the cars are represented by red LEDs on a playfield which covers only a small portion of the case. The audio consists of beeps. George J. Klose based the game on 1970s racing arcade video games and designed the hardware, with some hardware features added by Mark Lesser who also wrote the 512 bytes of program code.