Sinevibes tells us that Drift is an AudioUnit effect plug-in that applies infinitely-changing modulation onto sound level. Here's what they have to say about it...
Drift features a fractal-based modulation generator that produces endlessly developing waveforms which are unique per each audio channel, and have controllable speed, smoothness and intensity. This fractal waveform is then applied onto the sound level and allows you to create various stereoscopic effects like pan fluctuation, ever-changing crossfades, and chaotic tremolo. Combined with a very simple interface, Drift allows you to easily bring life into static sounds. Features
Amplitude modulator based on a dynamic fractal system with variable speed, smoothness and intensity.
Intuitive, resolution-independent user interface with graphical feedback and full parameter automation.