Do you worry that the ‘tin-tin-tappety-tap’ emanating from the headphones of the moron next to you on the bus could damage your hearing? Then worry no more. Technological help is at hand in the form of the Ear3 Sonic Threat Indicator:
Yes, it’s true. This techno-gizmo will set you back a whopping US$49.95 and do nothing to actually protect your ears from potentially damaging sonic waves. But you will know why you have gone deaf thanks to its rapidly flashing red light.
This one doesn’t quite cut it as ‘UsefulTechnology’. Your money would be better spent buying some cotton wool to stuff in your ears.