https://i.ytimg.com/vi/FdtskdgYE08/hqdefault.jpg
Blendfile: http://blenderdiplom.com/en/tutorials/all-tutorials/560-tutorial-volumetric-logo-reveal-in-cycles.html
Since Blender 2.70, Cycles can render volumetrics. This tutorial shows how to use a homogeneous volume and anisotropy to great advantage.
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