The light bounces around the inside of the box before it leaves through the paper diffusion
Woven fabric such as faux flowers
Woven fabric can be gathered, pleated, and otherwise transformed to bring shape to the light coming from the LEDs. Think of it as very flexible paper.
Knit fabric such as sweaters and scarves
Knitting is stretchier than woven fabric, and can be constructed in a way that gives the fabric more volume and varied texture.
Plush toys
While technically the outside of a plush toy is made from knit or woven fabric, I want to highlight the polyfill stuffing that can give shape to light from within.
Glass jars
Glass transmits light beautifully. Consider painting the inside with transparent glitter, fill it with transparent beads, or line it with a piece of paper.
Backlit laser-cut textile
Cutouts in an opaque surface with a strong backlight make for fun silhouetted effect.
LED underlighting/backlighting
Consider bouncing the LED light off a nearby surface, like the ground (underlighting), or backing board.
Laser-cut acrylic
You can etch clear acrylic to affect how it diffuses light.
Crinoline tubing
This sheer flexible tubular textile is just the right size for LED strip.
To read more about the sample projects shared in the video above, check out my website. To follow along and build your own LED diffusion methods, check out the following Digi-Key supplies: