October 8, 2008: Google's Gmail this week added a feature designed to help save indiscreet Gmailers from themselves: Mail Goggles, which asks for the answers to a few simple math problems before it will let an e-mail leave the out-box. The theory is that if the user is calm -- or sober -- enough to do the math, they're probably in a fit state of mind to send the message.

By default, Mail Goggles is active late at night on the weekends -- as its developer said on the Gmail blog, "That is the time you're most likely to need it." But for those who are especially prone to firing off e-mails without thinking, it can be set to be active any time, or all the time.

To use Mail Goggles, you'll need to have "Labs" enabled in Gmail. To turn it on, click on "Settings," hit the tab for "Labs," then enable Mail Goggles.