Sound Microscope is many things rolled into one. It's, first of all
a sound piece. It can also be both, a sound game, but most
importantly, a tool for teaching about the nature of sound.

Commissioned by iSAW as part of its commitment to education,
Sound Microscope uses a simple Google-Maps-Style interface
that let's you zoom in and zoom out on different regions in a
sound's digital spectral sonogram. It also lets you hear only the
part of the sound that appears on the screen.

So, with the main slider in the bottom-most position, you hear
the sound's full duration and frequency range. Zoom in and
click-drag the screen to explore the geography of that sound in
detail, audible components that are difficult to detect with your
naked ear.

+ info: http://www.isaw.info/sm/