This Hacker News comment by GuB-42 intrigued me: With ZWJ (Zero Width Joiner) sequences you could in theory encode an unlimited amount of data in a single emoji. Is it really possible to encode arbitrary data in a single emoji? tl;dr: yes, although I found an approach without ZWJ. In fact, you can encode data in any unicode character. This sentence has a hidden message󠅟󠅘󠄐󠅝󠅩󠄜󠄐󠅩󠅟󠅥󠄐󠅖󠅟󠅥󠅞󠅔󠄐󠅤󠅘󠅕󠄐󠅘󠅙󠅔󠅔󠅕󠅞󠄐󠅝󠅕󠅣󠅣󠅑󠅗󠅕󠄐󠅙󠅞󠄐󠅤󠅘󠅕󠄐󠅤󠅕󠅨󠅤󠄑. (Try pasting it into this decod...