The Tikk-Tekk Rainbow Measuring Device is designed for the visually-impaired and uses audible sounds to track measurements.
Two rings are slipped over the two index fingers and a measuring stick in between that loosens as it is stretched. A 'tikk' sound is made after every centimeter and a 'tekk' sound after every five centimeters. For added readability, the Tikk-Tekk also has embossed Braille readings as well as a digital display.
Implications - I think this is a great invention to help better the lives of those with vision impairment as they no longer have to rely on others in order to measure objects of their choosing.