If you do a search for the AR-7778 calculator on YouTube, you'll quickly find that it's a popular musical calculator that plays simple tunes when buttons are pressed. Japanese Twitter user @atarimae_400 has gained a following for his impressive hobby of being a musical calculator "pianist" by arranging a number of playing classic themes of popular anime, video games, and even J-pop.

Here's a few of @atarimae_400's awesome calculator performances!

Cruel Angel’s Thesis (Neon Genesis Evangelion opening)

Main Theme (The Legend of Zelda)

Opening Theme (Pokémon)

Zenzenzense by Radwimps (Your Name)

For more cool calculator tunes, be sure to follow on Twitter or YouTube.