When I ordered some more Jacquard paints from Dharma Trading (in their mini-starter sets, or what Jacquard calls Exciter packs), I also ordered a kit for sun printing from Setacolor. Then we proceeded to have mostly cloudy or even rainy weekends for almost a month. This weekend was still partly cloudy, but there was enough sun Sunday afternoon that I tried it out. I didn't have anything planned for the prints, so I just cut some ferns and leaves from the backyard.
I don't quite understand how this works. You paint the whole piece of fabric with one or more colors, press the leaves or other objects into the wet paint, and let it dry in the sun. I would expect that the fabric under the leaves to stay a brighter color and the parts in the sun to lighten up, but instead the paint migrates away from the covered area because it stays wet longer. This leaves a much lighter impression of the object, almost as if you had applied a resist first. But it is nice. I also added some salt, which makes bubbly designs.