Christoph Pöhler and Gottfried Hoffman take us on a tour through the world of snowflakes. The tutorial consists of two parts, the first one covering procedural modeling and the second one rendering.
Using a simple modifier set up, modeling a snowflake shape in Blender becomes really easy. In the first part of this tutorial, Christoph Pöhler shows how it's done in just 5 minutes (note that for a realistic snowflake model , the structure needs 60° angles everywhere, so keep that in mind when modeling):
The result can be used for simple winter backgrounds like this, or more elaborate ones. Both ideas are presented in the second part of the tutorial by Gottfried Hofmann.