Vu1 has developed a new, energy-efficient lightbulb that’s a bit different….not like the LED and CFL bulbs you see on the shelves today.  They’re using a technology known as Electron Stimulated Luminescence, or ESL for short.  ESL bulbs emit electrons which hit a phosphor coating inside the bulb, which then emits light.  Pretty simple in theory, and the result uses around 60% less energy than an incandescent bulb (and contains no mercury, unlike CFLs), at a reasonable price (approaching $10 once production ramps up).  Compared to LED bulbs, it uses more energy and doesn’t last as long, but LED bulbs have had challenges getting good color reproduction, and the ESL bulbs might have an edge there.  You can read more about it over at Vu1’s homepage, or check your local Lowes if you want to buy one to try out.