Ableton Live Racks
Live is fast, fluid and flexible software for music creation and performance. It comes with effects, instruments, sounds and all kinds of creative features—everything you need to make any kind of music. Create in a traditional linear arrangement, or improvise without the constraints of a timeline in Live’s Session View. Move freely between musical elements and play with ideas, without stopping the music and without breaking your flow.
More info: www.ableton.com