When I was heavily involved in music education I longed for a tool to create music notation in a browser. I even started a little development with a colleague but we never got anywhere near the service now offered by Noteflight. Here’s a basic example (I can’t embed it with WordPress, only link to it.)
It’s in beta at the moment but my simple 4 bars were easy to create with intuitive tools. As a demonstration tool of musical examples (chord movement, melodic shapes – many things related to music language) it is invaluable. The sounds are basic and playback lacks any finesse, but that is true of notation packages, where the look is the priority and the sound provides the bare essentials of pitch and rhythm.