I haven't seen anything recent on these. Any keywords to google? The key thing for a consumer electronics application is ease of getting the fuel. People don't want to have to head out to the shops to get it every few days, which is why rechargeable batteries are the current winner.
Try "MIT Micro Turbine Generator". That will get you to the base technology. I tried to find the DARPA Page, but it seems to have been buried. The MIT Technology has also got a lot smaller from the 2006 initial turbines, which were roughly the size of a quarter. They know measure less than 1cm on a side. The Generator that creates the electricity from these things is roughly the same size as the turbine. It basically looks like a DVD Motor (really flat and broad).
I saw them as a field power source for laser designator and weapon (a modified laser...
I would like to propose this as a thread for people to write in their predictions for the next year and the next decade, when practical with probabilities attached. I'll probably make some in the comments.