I’ve written occasionally about how LED lights will gradually displace incandescent bulbs in most applications over the coming decade or so, and this is already happening – look closely at the tail lights of that truck you’re passing, or the traffic light you’re stuck at, and also note how you can buy LED bulbs to replace your existing incandescent bulbs right now, they’re just a little pricey and a little dim for most applications. There’s news today that major progress has been made on the dimness front – researchers in Japan have managed to almost double the luminosity of LED’s. I think this means you’ll be able to manufacture a bulb that’s sufficiently bright to replace incandescents for most household uses. At what cost, I don’t know (and given that the inventor is leaving his research job to commercialize this, my guess is ‘not cheap’ to start), but it’s another step down the path.