I recently did a wall hanging designed by Castilla Cotton that is penguins getting Christmas lights ready to hang. Snowflakes are falling in the background.
The pattern called for hot fix crystals for some of the snowflakes, and I decided to give it a whirl. Turned out really cute, the crystals do add a lot. I also used them for the little penguin eyes.
While I probably wouldn't put them on a quilt, I'd use them on a wall hanging again.