tutorial:
http://www.blenderguru.com/videos/how-to-create-a-lightning-storm
By blender Fan Page:
https://www.facebook.com/pages/blender-Works/132831550129151
http://www.youtube.com/watch?v=DWJNTGt0jqI&list=UUxvOVADQm7jZKta5OIrAWlw&index=4&feature=plpp_video
