Keep an eye on Optalysys. Interesting things will probably come out of it.

Optalysys’s initial products will launch in 2017 and are expected to enable existing computers to achieve HPC-levels of performance up to an equivalent processing rate of 9 petaFLOPs – comparable to the 5th fastest computer in the world today. Following that we plan to pursue the design of larger systems capable of achieving multiple exaFLOPs by 2020.