PrimoMusic - An iTunes alternative made to manage iPhone/iPod media files
SunVox - SunVox is a small, fast and powerful modular synthesizer with pattern based sequencer (tracker).
SoundBetter - Marketplace for musicians and music production professionals
FamiStudio - FamiStudio is very simple music editor for the Nintendo Entertainment System or Famicom. It is designed to be easier to use than FamiTracker, but its feature set is also much more limited.
Gemtracks - Buy instrumental backing tracks and beats for $149! Get master ownership and copyright transferred to you once purchased.
MOTU Digital Performer - Get inspired, then refine your mix — all in a singular workflow.