Gmail Labs launched an application that enables users to simultaneously view multiple panes in Gmail without opening an additional browser window.

To activate, choose Gmail Labs for your Gmail account and click on "Multiple Inboxes" from the list of Labs options. Once enabled, a new Multiple Inboxes tab is added to Gmail settings. From there, users can choose up to five different panes to display to the right of the Gmail inbox, above your inbox, or below it.

By entering a code of your choice, you can select multiple inboxes when using standard Gmail search functions. For example, "label:friends" displays messages labeled as "friends." Multiple multiple attributes can be combined into a single pane: "is:drafts" or "is:starred" shows messages that are either drafts or starred, reports TechCrunch.

New users of the feature say it works best on a wide-screen monitor with relatively high resolution. Otherwise, the additional inboxes take up too much space, making it difficult to read the subject lines of incoming messages.

Gmail Labs was launched by Google last June as a place for Google engineers to show off the Gmail-related projects they develop in their "free" creative time. The applications it has provided include SMS chat, embedded autoplay video in Google Talk, and Mail Goggles, a filter that prevents late-night users from sending unintelligible, potentially regrettable emails while drunk.

Gmail was previously only available by invitation from current users, but opened to the public in 2007.