MilkyTracker - MilkyTracker is an open source, multi-platform music application for creating .MOD and .
OnlineSequencer.net - OnlineSequencer.net is an online music sequencer that allows users to create beats and music tracks.
OpenMPT - OpenMPT is a popular tracker software for Windows.
AudioSauna - AudioSauna is a full-featured audio workstation for making music online.
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.
Jummbox - A modified Beepbox that have more stuff then Beepbox. It can be used just like Beepbox. The features of Jummbox is the same of Beepbox's features, but Jummbox have more stuff to offer.