Yesterday Lockheed Martin announced that it believes it has made a breakthrough in research that could lead -- in only 10 years -- to a practical nuclear fusion reactor. Infinite energy from seawater!
You can read good coverage at Reuters, Aviation Week and Scientific American. Some popularized discussion of competing research here.
Of course, many are skeptical given the lack of publication of detailed results ... as fusion is always "30 years away" from commercialization. That is why the "10 year" timeline is interesting. It is short enough so the individual involved will actually be around, and at reputational and career risk, if they should be wrong.
And no discussions of cost. If the commercialized 100MW reactor costs billions of dollars ... this technology will lose out to solar PV/wind + storage.