Graphene has many remarkable properties, but one is that water passes through a graphene coating onto an absorbent surface as if it wasn’t there. Given the large number of people in the world without access to clean water, wouldn’t it be nice if we could make this:
Graphene drinking straw
The absorbent material provides a smooth surface onto which to apply the graphene coating. The graphene coating filters out everything except the clean drinking water. The sponge then provides a reservoir from which to suck safe drinking water. When we get to the point that graphene can be produced cheaply and easily, this could save many lives in developing countries, in disaster zones, and even be useful to save carried weight for hikers, sailors and the military.