Google Labs has introduced a new tool for inboxes, called Multiple Inboxes, which is available under the Labs tab in your Gmail account. Users need to enable the add-on in order for it to be available. The new tool will allow people to filter and label their mail in an organized list of their choice for easy browsing.
With the new addition to the Labs, users can customize their inbox to always display mail from different folders or with customized set labels. The feature can support up to 5 panes on the right, top or bottom of your inbox, as well as a customized number of conversations per display.
Here is a quick look at what the inbox can look like
(image courtesy of: gmailblog.blogspot.com)