A Botswana company that makes hearing aids for developing countries has shipped a small, solar-charged, ruggedized hearing aid specifically designed for use in sub-Saharan Africa:
The SolarAid is a hearing aid designed and built by Godisa Technologies, a Botswana company founded to make low-cost hearing aids for the developing world. The SolarAid system combines a small hearing aid and a lightweight solar charger; Godisa developed the first No. 13 rechargeable button battery for the system. Godisa is Africa's only hearing aid manufacturer, and the only one in the world making hearing aids specifically for the sub-Saharan Africa environment.
(Thanks, Jamais!)