Gmail introduced a lab edition in June with 13 features. Over the time they kept adding these features and here is post listing latest lab features.
But before exploring further, for those who missed these lab features completely, these can be activated selectively by going to Lab tab under Gmail Settings.
And here are some cool and latest features:
Move the chat box to the right side of the inbox. This is good if you have longer chat list which pushes your labels box below. By the way there is a small “options” link below chat box, which let you resize it to 4 different sizes.
Move the labels box to the right side of the inbox. This is good if you use labels a lot. You can move labels or chat or both boxes on right side.
Make ‘Reply to all’ your default option for responding to emails. Good for developers who collaborate on projects as you will never forget copying to someone in group.
Quote the text you have selected when you reply to a message. This works best if you use keyboard shortcuts. This type of quoting replies is quite popular with people who spend lots of time on forums or mailing lists.
Allows you to reorder the items in your navbar using drag and drop. Some Lab features adds extra boxes to your navbar. Enabling this feature can save a lot of scrolling in some cases.
Forgotten Attachment Detector
Prevents you from accidentally sending messages without the relevant attachments. Prompts you if you mention attaching a file, but forgot to do so. There was a greasemonkey script to do this from long time.
Lets you specify starting and ending dates for the vacation autoresponder. This is good for guys who forget to setup vacation responder in last minute rush. Using this you can set a vacation responder as soon as you make reservations for your vacation.
Lets you create your own combination of colors for labels. Instead of choosing one of the standard colors from the label dropdown menu, click on Add custom colors. Pick your combination of colors, hit Apply, and enjoy.
Tired of spending all that effort to click on the more actions menu every time you want to mark messages as read without reading them? Now just enable this lab and that is just a button click away!
Enable keyboard shortcuts and hit ‘g’ then ‘l’ to display a popup for selecting a label to go to. Quite useful for guys who use labels a lot. Personally I will use labels more often now.
Let us know which lab features you are enjoying and which one feature you are missing in Gmail. Personally, I miss to-do list a lot in Gmail.
Related: 13 More Gmail Lab Features