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[link]There isn't a whole lot to say about this tutorial: obviously, it's a guide to the variety of emotions the human face can express, with as many pointers as I could think of to help you understand how the different parts of the face (and body) are articulated in connection with specific feelings. It was a fun tut to make, requiring more intuition and observation than research.
The usual disclaimers apply: no part of this tutorial may be reproduced under any shape or form, the tutorial may not be reposted anywhere, etc. You can save or print it for your own private reference.