This Wired article reports on how financial analysts are using new technology that converts stock market fluctuations into sound. They call it 'auditory display software'.
The technology, which comes from a Dartmouth College spinoff called Accentus, aims to help traders deal with information overload. Typical traders monitor a half dozen or more computer screens filled with raw data, flashing numbers, and color-coded pop-ups. It's enough to max out anyone's visual cortex. But a trader's auditory cortex has plenty of unused processing power.
This technology can have a number of other interesting applications where real time data has to be monitored.