Fast, tiny, lossless image compression
There are countless image compression formats, and the world likely doesn’t need more. However, Dominic Szablewski was tinkering around with compressing RGB images and came up with his own lossless, super-fast, super-tiny compression algorithm called the Quite Ok Image compression algorithm.
While this is somewhat interesting in itself, the comments have a great discussion of how image compression has gone through a whole history of developments.