LMMS - Make music with a free, cross-platform tool
Anvil Studio - Free Windows multi-track MIDI/Audio recording & editing, VST Effects & Instruments, automation. Options for Sheet Music printing, music theory, ear training.
Cakewalk - The next generation of SONAR, the world's finest and most powerful DAW - now FREE.
Sekaiju - "Sekaiju" is a free, open source MIDI sequencer software for creating and editing MIDI...
Bosca Ceoil - A free, easy to use tool for creating music.
Finale - Finale, the world standard for music notation software, lets you compose, arrange, notate, and print engraver-quality sheet music.