This Vice interview with designer Daan Roosegaarde is an interesting look at the intersection between fashion and technology:

I traveled to a few electronics manufactureres, and at one of them I saw something lying in the corner, covered in dust, and I asked what it was. My guide told me, “It’s rubbish, all this fabric does is turn from white to transparent.” I bought it and started from there...

What sort of people actually wear these dress?

We made a version for a wealthy lady who lives in Los Angeles. She's married but has a secret lover. Basically, we made a dress that looks completely normal but recognizes the voice of her lover. When he says a particular set of words—which, by contract, I'm not allowed to repeat—the garment becomes transparent.

Of course, the last interaction most Americans had with reactive clothing was Hypercolor t-shirts. But it's hard to imagine that this kind of fashion technology won't eventually trickle down to the middle class,even as a gimmick. And one day, the gimmick might be really useful: How many t-shirts would you really need, if those t-shirts could change color to suit your mood and your outfit every morning?