You send a message to your coworker Avery, but then you start getting back messages from other people: "did you mean to send this to everyone@?" The messages pile up, people replying-all to ask what's going on, people replying-all to ask to be removed, people replying-all to ask others to stop replying-all. You curse Mr. and Ms. One for their poor naming choice, curse your fingers for screwing up again, and settle in to ride out the email storm. What else can you do?

If you catch one of these early enough, however, you can head it off before it spirals out of control. Use reply-all, but with everyone moved from "To:" or "Cc:" to "Bcc:". Do this as soon as you realize the problem, before the storm goes exponential, and with luck people will reply-all to your most recent message instead of any of the earlier ones. These replies will go only to you, so while you'll still get some annoyed and confused emails they won't compound.