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A Beginner's Guide to Effective Email: Acronyms & Jargon
An interesting and fairly detailed list of many of the acronyms that are used in email. Also discusses some unique internet/email "jargon," such as "spam."
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A Beginner's Guide to Effective Email: Gestures
Another site giving advice to beginning email users; this one deals with gestures in emails, such as smileys, pause equivalents, and creative punctuation.