Here's just a short list of what I found searching the site for 20 minutes. Most of the examples, people had to take a screen shot of what they were explaining or just put the note letters instead of visualizing the music.
- http://music.stackexchange.com/a/1166
- http://music.stackexchange.com/a/40222
- http://music.stackexchange.com/a/22242
- http://music.stackexchange.com/a/16999
- http://music.stackexchange.com/a/33950
- http://music.stackexchange.com/a/14783
- http://music.stackexchange.com/a/583
- http://music.stackexchange.com/a/23977
- http://music.stackexchange.com/a/4945
- http://music.stackexchange.com/a/6919
- Pentatonic scale with a sharpened 2nd note, any name?
- http://music.stackexchange.com/a/12074
- Are accidentals in the key signature and measure additive?
- Playing arpeggio on black notes with white note third
- What would be the proper fingering for these 2 small parts?
- How to correctly invert non-compound greater-than-octave intervals?
- Swing feel - are triplets and 8th note notations rhythmically the same?
And from the first page of questions :
- A-minor scale has different notes when descending
- Which scales are used by Tom Morello?
- Why do the notes of Melodic-Minor Scale change when you play it in descending order?
There were another 3 on the first page that might have benefited from being able to write notation, but these were the clearest cases.
