Mario Day, which occurs every March 10th (Mar10, Mario, get it?), originally started as an inspired fan's own creation on social media. However, others including Nintendo liked and participated in it, and now the holiday is celebrated worldwide each year.
This year I celebrated Mario Day by playing Mario Kart 7 for Nintendo 3DS, listening to fan-composed MIDI music renditions of the tunes of Super Mario Bros. 2 USA from the Video Game Music Archive / VGMusic.com / VGMA, and making pixel art of the Mario "M" letter logo with the Android app, Pixel Artist.
Please see the attached pixelated image that I included with this post to take a look!
How did you celebrate Mario Day?