Audio tool developer Sseyo has released a free plug-in for Dreamweaver that allows interactive audio to be added to Web pages. The audio pieces are embedded into pages as text "vectors", which are often less than two or three KB for an entire piece of music or sound effect according to Sseyo. The audio pieces can be used as background music or launched in response to HTML or Flash FSCommands. Music can also be altered dynamically in real-time due to user actions or other page events. End users must have the Koan Audio plug-in installed to hear the sounds and music, which is only available to Windows users. The Koan Dreamweaver Extension Set is only 175KB and comes with 100 free audio clips.