For the last six years or so, I've worked on a complete and comprehensive system of transcription-based shorthand which takes its inspiration primarily from the abbreviationes of the medieval scribal tradition. It's tailored primarily for writing in English, though it's useable in any language that uses the Latin character set. It comprises about 150 individual characters, though a sizeable chunk of those characters are diacritics that can combine with others to form a very flexible, dense, and aesthetically pleasing system.
I've documented this system in a slightly less-than-mature form; it's closer to feature complete now. Every so often I consider the best way to publish the system for wider consumption.