I have been predicting that harnessing the characteristics of photons and light energy is going to be the source of many of the most significant innovations we will see in this century. More support for this observation comes from an article at kurzweilai.net, that discusses how light might replace electrons to create faster, smaller and more efficient computers.
Optical computing is not new. However, its practicality has been hampered by the fact that it is difficult to get photons to interact at a scale comparable to that of electrons. That means that optical computers need to be larger than electrically-based systems. The size limitations have also prevented systems from being purely optical. Instead, they have been optoelectronic, requiring electrical energy to be converted to light energy, then back again. System efficiency is severely degraded because of that.
Now, a team at Imperial College London has been able to squeeze light into a channel that is much smaller than has previously been possible, such that photons can interact and be manipulated to generate binary data at the same scale as electrons. If the technology can eventually be commercialized, it promises computers and other devices that will be smaller, faster, more efficient, and with much greater bandwidth than is currently achievable.