• Thou shalt include a clear and specific subject line.
• Thou shalt edit any quoted text down to the minimum thou needest.
• Thou shalt read thine own message thrice before thou sendest it.
• Thou shalt ponder how thy recipient might react to thy message.
• Thou shalt check thy spelling and thy grammar.
• Thou shalt not curse, flame, spam or USE ALL CAPS.
• Thou shalt not forward any chain letter.
• Thou shalt not use e-mail for any illegal or unethical purpose.
• Thou shalt not rely on the privacy of e-mail, especially from work.
• When in doubt, save thy message overnight and reread it in the light of the dawn.

  And, here's the "Golden Rule" of e-mail:

• That which thou findest hateful to receive, sendest thou not unto others.

Ten more ....