Signal processing in the HiFi devices is fully symmetrical.

ENGADGET: Sennheiser unveils HDVA 600 analog headphone amp, asks for $1,600

Slowing down light may have many practical uses in communications, signal processing, television displays and night-vision devices.

BBC: A Bose-Einstein condensate: It slows down light

Nemesysco's devices use a series of patented signal-processing algorithms that can differentiate between a "normal" voice and a"'stressed" voice.

CNN: Behavioral screening -- the future of airport security?