Frederik Steinmetz demonstrates how to create a realistic Hoar Frost in Blender Cycles. Check out the complete tutorial for Creating Realistic Hoar Frost in Blender Cycles here.
From the tutorial description: This is Blenderdiplom’s way of saying: have some nice winter holidays. In this tutorial Frederik Steinmetz will demonstrate how to set up a beautiful macro scene consisting of a few frost-covered plants with a nice backlighting effect. It’s rendered in Cycles with a little compositing. Enjoy!