What great new inventions will be created in the next 100 years?

 1. Energy. Any new invention that can provide cleaner or cheaper energy will certainly be a great invention. Cold fusion has always been the "holy grail" of energy research, but perhaps something else might solve the problem. 2. Transportation. If something can get us around more efficiently and effectively than cars do, it would certainly change the world we live in. Also, anything that might make space travel more feasible would be nice. 3. Information technology. Computers will continue to get smaller, and nanotechnology and quantum computing will open up a vast array of possibilities. Computers may ultimately cross the line into cybernetics... someday you may be able to crunch numbers, write papers, or surf the net just by thinking about it! 4. Medical technology. Again, nanotech will open a lot of doors. Picture microscopic machines that can enter a cell and repair it from the inside, or select and destroy cancer cells or viruses. Any invention that cures disease would be a "great" invention. Also, I'm sure we will have a more advanced understanding of genetics in100 years, and our ability to understand and manipulate the human brain might also take some quantum leaps... for better or for worse. 5. Food/water production. Famine is always an issue and will continue to be. Find a way to meet the world's food and water needs, and you'll get your Nobel Prize for sure! 6. Entertainment. Media has really grown just in the past10 years, with music players getting smaller and tv screens getting flatter with higher definition. Holographic displays may become a possibility in the reasonably-near future. Also, interfaces like Nintendo Wii have a tremendous amount of room to grow... just the Wii itself has a lot of possibilities that have yet to be tapped. You could use it to train people to do their job, or to teach people martial arts or a musical instrument or how to dance... it will never replace the real thing, but it can be a cheap and fun alternative that may become more practical as the technology improves. 7. Materials science. Things like steel and concrete could become a thing of the past as polymers and ceramics become more easily produced. Materials may become lighter and stronger, allowing for new innovations in architecture and civil engineering, as well as everyday items like clothing and vehicles. If you could reduce a car's weight by50% without sacrificing safety or performance, think of the impact on gas mileage!