Shapeways is developing a new material called Elasto Plastic.
It's just what it sounds like, a stretchy, flexible, 3D printable material. The possibilities for wearables like jewelry and shoes are enormous- and the medical implications for a material that looks and behaves like cartilage are incredibly exciting.
Earlier today Materialise announced that their flexible printing material is now available to all users on a trial basis.
Materialise has a history of working with high-end designers and couture, as opposed to Shapeways' more egalitarian, any-Maker-can-play approach. So their product, TPU 92A-1, made its debut on the catwalk during Iris van Herpen’s Voltage Haute Couture show at Paris Fashion Week. You can see the dress being made!
I look at the fun designers and artists are having with 3D printers, and wonder where this sea change in artifact production will fit in fashion history.
Is it like the Jacquard Loom or more like home sewing machines becoming widely available? To the average creative person, 3D printing may work in clothing and accessory design like Sculpey/Fimo - a way to make small decorative things easily and cheaply.
Will the next stage be designers be buying home 3D printers and making signature clothing components, for people to add to their projects? Perhaps custom monogram buttons, or flexible bra cups made to your measurements, to sew into a bustier?
I recently bought some custom digitally embroidered lace pieces from a woman on Etsy. I told her what colors I wanted and she programmed her machine to run them up. She uses commercially available patterns, probably buys the design files from a company like Urban Threads.
Soon enough, artists and designers will be selling print design files so that people can print jewelry or shoes on their own home 3D printers.
Flexible materials make this profoundly more useful and interesting. 
At Maker Faire, the guys from Deezmaker gave me a stretchy bangle made of PLA, which used the strength of the material and sheerness of its output to flex very nicely. But that's designing around material, not designing to it. Want Vivienne Westwood jellies? Buy the file, print your own!
These Nicholas Kirkwood Beatrice shoes with insane lacquered laminate heels cost £540- but you could 3D print something like this easily. And hopefully soon, I will!