Super Mario Maker is a fantastic creative tool for fans of the franchise, and Nintendo's promoted it through limited editions, plenty of marketing and neat extras like the pixel-style amiibo, along with New 3DS cover plates in Japan and PAL territories. It's not quite done yet, though.
As plenty of fans around the web have spotted, there's now an official website that allows you to customise your own wallpapers for PCs / laptops, or indeed smart devices. There are limited items to choose from across all of the templates found in the game, so that's covering four Nintendo game styles and various stage backgrounds.
To do this you head to http://mariomaker-wp.nintendo.co.jp/, then scroll down and select the image of a PC monitor or smartphone. Though the site's in Japanese it's self-explanatory, with familiar icons from the game; when you're done with your creation click on the Coursebot logo and it'll generate a solid image of your wallpaper that you can save and share on social media.
It's a pretty fun feature and well worth checking out.