I'd still be afraid to collect mushrooms myself: Edible fungi chart. If the world is ever covered in darkness, the only plants that will grow without sunlight are mushrooms. Stick this in your survival guide!
This photo jumped out at me from my FB feed. The colours alone had me. I'm a huge fan of the naturally occurring blue hues, especially in insects and fungi. These little, blue mushrooms are awesome. - Photo courtesy of Gardening