Currently, most computers are made of silicon. Silicon is the most plentiful material on earth, mostly in the form of sand and rock. Unfortunately, silicon is limited in the temperatures it can endure, and modern computers dissipate more and more heat as they get more powerful. This is limiting the development of further computing power. In addition, most CPUs must be quite flat in order to be properly cooled.
But silicon is not the only possible material to build computers out of. A number of research teams around the world are conceiving of CPUs cut from synthetic diamond. Such a CPU could endure temperatures of thousands of degrees, would naturally conduct heat away at high speed, and could have an extremely tall, 3 dimensional structure. A thousandfold increase in processing power could happen easily.
Diamond mining companies are not pleased by these developments. Mined diamonds have uncontrollable impurities that ruin them for this purpose, and also cannot be outrageously large enough. In addition, synthetic diamonds might weaken the value of their own diamonds, since synthetic diamonds could arrive to any specification for cheap. An engagement ring with a gem the same color as your partner's eyes? No problem. A ring whose gem is made from the ashes of a family member who recently and tragically passed away? Can do.
Elaborate tests have been made by mining companies to distinguish laboratory-cultured diamonds verses naturally cultured, with the hopes that they can then encourage consumers to prefer naturally made. I think that a girl that would reject a laboratory diamond is not a girl for me.
How far away is diamond computing? A ways. An estimate of 10 years has been issued, but I suspect it is like the 50 year estimate for fusion power, it will remain 10 years away for another 10.