When's the last time you got an email from a stranger asking, "Are you sure you meant to send this to me?" and promptly realized that you didn't? Sometimes these little mistakes are actually quite painful. Hate mail about your boss to your boss? Personal info to some random guy named Bob instead of Bob the HR rep? Doh!

"Got the wrong Bob?" is a new Labs feature aimed at sparing you this kind of embarrassment. Turn it on from the Labs tab under Gmail Settings, and based on the groups of people you email most often, Gmail will try to identify when you've accidentally included the wrong person — before it's too late.

If you normally email Bob Smith together with Tim and Angela, but this time you added Bob Jones instead, we'll warn you that it might be a mistake. Note that this only works if you're emailing more than two people at once.

While we were at it, we also changed the name of "Suggest more recipients" to "Don't forget Bob" — the two related Labs features just kind of went together better this way.

If you want to test "Got the wrong Bob?" out, try faking a mistake like this:
1) Think of three people you often email together.
2) Compose a message to two of them.
3) Start typing the third member of the group (for help you can use one of the people we suggest in "Don't forget Bob"), but then auto-complete on the wrong name.

If you have suggestions please let us know. And if "Got the wrong Bob?" happens to save you from making a really bad mistake, we want to hear about that too.