When you receive copies of emails that you previously received because those people who were cc'd on the original sends them to you thinking you never received the first one.
Very annoying as it needlessly floods your inbox.
Damn, I have 49 emails in my inbox but luckily it looks like many of them are simply echo emails.

Dude, please stop with those echo emails, I recieved them already.
by Kid Pseudo September 10, 2008
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