It's a funny conversation piece, sure, but Gmail Labs' feature may be one of the least useful options introduced to the service. Designed to keep you from sending messages you'll regret the next morning, Mail Goggles makes you answer a couple of simple math problems before your e-mails will be delivered during late-night hours. Being that you're at a computer, though, you'd have to be pretty inebriated not to be able to find the calculator function and get past the guard.

2. E-Mail Addict

I'm plenty familiar with the idea of , but Gmail Labs' option isn't exactly like rehab. EA, as the kids call it, blocks out your screen and makes you invisible for 15 minutes once you click it on. All you have to do to get around it, though, is hit refresh. This one's nice for its novelty and amusement factor, but its practical application is pretty limited.

3. Undo Send

File this one under "great idea, less than stellar execution": Gmail , as you might imagine, allows you to stop a message from going through after you've hit the "Send" button. It sounds useful enough, but here's the problem: You only have a five-second window to use it. When it comes to realizing you've made a mistake in e-mail, five seconds isn't much. Add some extra padtime (or, better yet, the option to specify how much padtime you want), and Undo Send would be brilliant.