Artangel: Mixed media crumpled tissue technique - tutorial - basically, glue tissue paper over a canvas, let dry. Paint, let dry, then rub pastel or chalk over the surface to highlight the texture. Would be an awesome way to vignette around a painting.
Watercolor on tea bags ~ Tea bags were torn open glued to watercolor paper. Paper had been stamped beforehand with text, then designs were sketched painted over the tea bags along with the dragonfly stamp. Great for art journal or altered books.