Once tabbed browsing became mainstream thanks to Firefox and other tabbed browsers, I knew it would only be so long before people tried to find ways to make tabs useful for other applications, and it looks like the makers of Thunderbird are going to be throwing tabs into their e-mail client software. Tabbed e-mail messages? Odd, but maybe useful.

A developer has added tabbed browsing of e-mail messages to Mozilla’s Thunderbird e-mail client, mimicking one of the most popular features of the Firefox and Opera Web browsers.

It is unlikely the feature will be found in Mozilla’s imminent release of Thunderbird 1.5 — currently in testing — but software developer Myk Melez has put test versions of Thunderbird online with the tabbed browsing feature included.