Snake in a QR Code
If you want to see a variation of this concept in the wild, in active use by lots of people, check out PICO-8 cartidges.<p>PICO-8 is a virtual game console. I.e. it's an emulator for an oldschool game console that doesn't exist in reality. It's designed to be easy to code for while maintaining the limits and aesthetics of old game computers<p>PICO-8 games are, of course, distributed on cartridges. However because it's a virtual console, the cartridges are virtual too: they're PNG files.<p>Try browsing PICO-8 games here: <a href="https://www.lexaloffle.com/bbs/?sub=2&cat=7" rel="nofollow">https://www.lexaloffle.com/bbs/?sub=2&cat=7</a><p>Press the play button the play a game right inside the web browser, but be sure to click the little "Cart" link right below the playing area to see what's going on. You'll see it open a little PNG file.<p>That PNG file <i>is</i> the cartridge. It contains the entire game.<p>The file format is explained here: <a href="https://pico-8.fandom.com/wiki/P8PNGFileFormat" rel="nofollow">https://pico-8.fandom.com/wiki/P8PNGFileFormat</a>. Obviously, because PICO-8 carts are purely digital, the format doesn't need any of the contrast, the error correction features or the orientation markers that QR-codes have. You can't take a picture of a cart with your phone and play it. You need the exact same, byte-for-byte PNG file. But it's still super cool.