The Sound Reactive Nightgown uses Flexinol, a shape-memory alloy that returns to its original form when it is stimulated. If you yell or speak loudly in the vicinity of this item of apparel, it starts lifting up the hem.
(Sound Reactive Nightgown video)
Fans of JG Ballard recall the fashions of Vermillion Sands, made from bio-fabrics that react to the emotions and moods and noise-level of those nearby:
The racks of gowns itched and quivered, their colors running into blurred pools. One drawback of bio-fabrics is their extreme sensitivity. Bred originally from the gene stocks of delicate wisterias and mimosas, the woven yard have brought with them something of the vine's remarkable response to atmosphere and touch. The sudden movement of someone nearby, let alone of the wearer, brings an immediate reply from the nerve-like tissues. A dress can change its color and texture in a few seconds, becoming more decollete at the approach of an eager admirer, more formal at a chance meeting with a bank manager.
The first time I encountered the idea of a shape-memory metal alloy was in the amazing 1966 short novel Babel 17 by Samuel R. Delany:
He raised his hand. "Suppose you needed a gun"—in the Barons's hand now was a sleek vibra-gun of a model later than she had ever seen — ''or a crescent wrench." Now he held a foot long wrench. He adjusted the opening. "Or a machete." The blade glistened as he waved his arm back...
An unexpected property of polarized matter is tensile-memory." They moved toward an archway Into the next room. "Annealed in any shape for a time, and codified, the structure of that shape is retained down to the molecules. At any angle to the direction that the matter has been polarized in, each molecule has completely free movement. Just jar it, and it falls into that structure like a rubber figure returning to shape." The Baron glanced back at the case.
"Simple, really. There"—he motioned toward the filing cabinets along the wall—"is the real weapon: approximately three thousand individual plans incorporating that little polarized chunk..."
(Read more about Tensile Memory Polarized Matter)