Howard Weinstein, is the man behind the invention of this hearing aid, specially designed for the world's poor. He made this possible with a series of grants and help from hordes of deaf individuals, some 20,000 folks in 30 countries are currently using the solar-powered devices. Though SolarAid is not much different than the average hearing aid in function, however this is powered by the sun, eliminating the battery problem altogether.

Weinstein was even able to put the very same deaf people to work, since the skill it takes to master sign language—"acute hand-eye coordination"—perfectly translates to soldering and other microelectronics work.

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