http://www.core77.com/blog/object_culture/brilliant_waterbased_eyeglasses_for_the_masses_no_optician_required_12220.asp
Eyeglasses that use water as a lense. Apparently they are super cheap to produce so they could easily be distributed to all the poor people with bad vision. It took a physics professor at oxford to invent these, I think the principles of water magnifying things were discovered hundreds if not thousands of years ago. Kudos to him for finally making them though.