WaveShop - Open source audio editor
OnlineSequencer.net - OnlineSequencer.net is an online music sequencer that allows users to create beats and music tracks.
TwistedWave - TwistedWave is one of the unique audio editors that allow you to edit your music file online without any installation.
AudioSauna - AudioSauna is a full-featured audio workstation for making music online.
Audacity - Audacity is a free and open-source audio production software suite that includes a surprising array of editing tools and recording systems.
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.