NtEd - Music Score Notation editor.
Sibelius - Sibelius is a virtual score creation tool which allows composers to easily create new piano scores, developed by Avid.
music21 - Music21 is a Python-based toolkit for computer-aided musicology.
LilyPond - GNU LilyPond is a computer program for music engraving.
ABCexplorer - ABCexplorer is a musical creation utility that comes with advanced support to create, edit, play, convert and manage musical files with ABC text format support.
MEFA - MEFA offers education programs, tax-advantaged savings plans, low-cost student loans, and expert guidance in financing for students and their families.