Over the past few years, someone figured out how to produce flexible electroluminescent displays. The technology is showing up in all sorts of things:
Badge Examples
Sheet and cable examples.
Who came up with the stuff, and how is it made?
Here’s a short history of electroluminescent displays, but as of 1999, it doesn’t mention the flexible material.
Bump
If I had to guess, I’d say it most likely involved the use of tritium (an isotope of hydrogen), possibly microencapsulated, and some sort luminescent paint or dye. Radioactive tritium has been used in various applications, such as watch dials, for a few years now. It’s a very expensive substance, but so little needs to be used to achieve the desired effect that it’s relatively practical.
If tritium was involved, I don’t think there’d be a need to supply AC power, which the webpage says is required.
Not to mention the animated bits in the badge link. It’s kind of hard to turn tritium on and off like that. I probably should have read the links first, huh?
Or at least layed off the brown acid. 
These displays are likely some sort of variant on the backlit displays for notebook pc’s, but I don’t grok how they get them all flexible and unformly lit without a fancy (and finicky) set of electrical contacts etc. etc.
Surely Electronics Design News or one of the other trade magazines has covered these things within the last couple of years?
There are a number of electrically conducting polymers that can be used to make flexible EL devices – polythiophene derivatives coated onto plastic sheets come to mind. I can almost guarantee that tritium is not used in these things. It is highly radioactive.
Once upon a time they used to make glow-in-the-dark watch dials using a mixture of radium chloride and zinc sulfide (a scintillator). Not so anymore 
Putting the search terms “electroluminescence flexible” (not using the quotes) in google came up with some promising, detailed technical refs. Heavy on the “how,” less on the “who.” That should keep you busy for a while, Squink.
Yeah, I did that before posting the question. Wading through all the tech gobbledegook gave me a headache, so I figured there’s be some engineers here who’d worked with the stuff, and knew something about it. Not much luck with that plan so far, so I may have to go back to wandering the unfamiliar jungle.
Polythiophene ehh? That might be a start.
I realize this isn’t much help – but just let me reminisce. Some friends and I were working on a science fair project in the early 1960’s on electroluminescent panels. It was thought that future houses would be lit by walls of them instead of bulbs. (Future houses, like in the 1970s, when we would all be driving turbine or electric cars!)
The only problem with doing that then was the production cost; back when a single transistor cost $1, and this was a semiconductor project. But we all could see that it was only a matter of time before these costs dropped drastically. I wonder why we don’t have E-L wall panels in all homes now?!
The only thing I recall is there were three basic parts to the panel. An opaque or reflective backing, a transparent or translucent dialectric, and a transparent cover sheet. Powered by AC, the electro-chemical interaction between the panels produced light. The higher the frequency, the more light. The closer together the panels, more light. Chemical composition or optical filtering controlled colors. and the light was non-heating.
One of us claimed to have baked some homebrew panels in his oven, but I never saw the results.
I imagine the flexible ones differ primarily in the material; the electrical principles would be the same regardless.
That headache? 
Take two aspirin and post in the morning.