Although Gmail has been in existence since 2004, Gmail Labs were only introduced in mid-2008. Gmail Labs are arguably what makes Gmail extremely powerful as a mail client, akin to how web browsers like Firefox and Chrome can be extended via extensions.

Here is a collection of labs that you can use today to become more productive using Gmail and processing your e-mail.

1. Canned Responses. Canned Responses allow you to create a message that you can easily re-use when replying to e-mails. For example, if you use your Gmail account for your business, and regularly send the same response to a common inquiry, then you should absolutely use a canned response to save yourself the time of re-typing that message each time.

2. Custom Keyboard Shortcuts. Although Gmail comes with keyboard shortcuts for common actions already built in, it may be difficult to remember especially if you use shortcuts in other programs. This lab allows you to modify those keyboard shortcuts to your own liking.

3. Default "Reply to All". Save yourself an extra click by enabling this lab. It changes the "Reply" button in the top-right of the message to "Reply to all".

4. Message Sneak Peek. This lab lets you see a bit more of a message without having to open up the message completely. This is useful when you have a lot of emails that you delete quickly. Either right-click, or hit the shortcut key (default is 'h').

5. Quick Links. This is one of my favorite labs. While Gmail's search can be quite powerful and fairly fast, if you find that you perform the same searches repeatedly, this is a great way to save them in something called a Quick Link. Once saved, in future, all you would need to do is click the quick link in the left sidebar, and Gmail would pull up that saved search.

6. Send & Archive. Send and Archive saves you a click and helps you process email faster by changing the Send button to both send and archive the message thread. You should already be using archiving to get your inbox down to zero.

7. Superstars. If you use Gmail's starring to highlight certain emails, you may want more than just a single gold star. Superstars gives you the option to select a number of different colors and icons including question and exclamation marks.

8. Undo Send. Undo Send is potentially a lifesaver that I've now used more times than I can count, despite being a rather careful e-mail sender. Essentially, it gives you a window of time after you hit Send during which you can 'undo' and retract the message before it's actually sent. This is great for those times that you entered the wrong recipients or had a thought about the content of the e-mail the split second after you hit the send button.

Gmail Labs has many more extensions that you may find useful, but start with these 8 and see if you don't spend less time processing your e-mail every day.