Parmotrema perforatum, the "perforated ruffle lichen", on a fallen hardwood branch, central Florida. This lichen is imported into Afghanistan for medicinal use. In India, it is thought to have a wide variety of healing properties.
There have been a bunch of books released lately, featuring beautifully photographed things from nature, both life size and micro-sized. The latest I've had the priviledge to flip through is the magnificant book, seeds, the time capsules of life.