UN will build statues for invnetors, not to mention nobel honor:
CO2 absorbing device mimicking plant photosynthesis
cheap/efficient electricity car (nuclear power being the ultimate source)
cheap/efficient solar power
cheap/efficient underground traffic (not just metro/tube)
artificial blood ( i always dream kind of a powder for long term storage, when needed just add sterile water)
optical fiber communication
cheap/efficient water recycling and purification
cheap/efficient nicotine substitute
....