Extract a file per book in your kindle My Clippings.txt.
Usage:
kindleclip <CLIPPING_FILE> <OUTPUT_DIR>
This will go through all your kindle clippings and export notes to a file with a somewhat-sanitised filename (lowercase, replace ' ' with '-', remove some punctuation).
If the note was a NOTE (rather than a highlight), the text 'NOTE FOR PREV' will be exported above a note, so that it's easier to link highlight and note.