This is probably more useful than GMail's last experimental new feature (
Mail Goggles):
Canned responses (see
Official GMail blog). You can now save a reply you're writing as a "canned response" and then quickly select one of these responses when you're replying to a future e-mail.
You can also have your GMail filters auto-reply to messages for you with these reponses. I quickly set up a filter, for example, to reply to people who send me an e-mail with "pitch" in the subject line with a message asking them to reach me on my work account.
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