Well, TMB went and made the Firefly, a product I drew the basic idea for about a year ago, though mine was based on an EL wire instead of LEDs to get the true “glowing filament look”.
The basic idea is to take a power-hungry but beautiful 3200 Kelvin light source and get the same light and look out of it with an efficient emitter like an LED. This would be pretty easy to do with a frosted bulb, which could hide and diffuse the light source, but much harder to emulate the traditional “Edison bulb” look because the visual appeal of those is based on a large, glowing filament. TMB has made an interesting hybrid using what looks like fiber optic strands inside the light to get the filament look at suitable viewing distances. I haven’t seen these in person, but I imagine they’re probably pretty good at fooling your eye from greater than a few meters away.
I wonder how hard it would be to take the idea even further and get a true Edison bulb “look” – large glowy filament – using one or several strands of fiber optic cable. I imagine the light dropoff inside the strand would lessen the effect, but there might be some way to compensate for that, at least enough to convince someone looking at it from a few meters away.