This plug-in integrates Google Reader into Gmail. Hide the Reader\'s nav, since one appears in Gmail via the plug-in, and maximize your reading space. (Credit: Better Gmail 2)

Better Gmail 2 is a Firefox extension that collects a bunch of Gmail customization scripts from Greasemonkey under one control panel. The latest update, to Version 0.3, brings Better Gmail 2 mostly up to speed with features that were in the original Better Gmail, but had to be abandoned when Google rewrote Gmail's code last November.

The biggest of the latest additions include a revamped insertion of Google Reader into the Gmail user interface. This is not merely a rehash of what came before, but a better-looking, faster-loading UI that makes switching between Gmail and Reader seamless.

There's also a new rollover highlight for messages. The highlight colors aren't customizable, but it's still a great little tool for grabbing your attention, and the colors change depending on whether the e-mail you're currently mousing over has been read or not. One-click conversations have returned, too. This tool inserts a small head-and-shoulders icon in between the star and the e-mail sender. Click on it to show all recent conversations with that person.

Message highlighting and viewing recent conversations are two useful features in this extension. (Credit: Better Gmail 2)

Skins are back, with two flavors for those who get sick of Gmail's layout. "Grays and blue" gets rid of most of the white in the interface in exchange for a more muted palette, while the Gmail Blue Skin leaves the whites intact but creates different shades of blue backgrounds behind the navigation options. Both include substantial font changes.

The plug-in's other features are nothing to sneeze at, either. You can forced encrypted connections for security, change the attachment icon to reflect the file type, modify keyboard shortcuts, automatically show message details, and more. Better Gmail 2 is a must-have Firefox extension.

Also, don't forget to check out our Top 10 Firefox Extensions of 2007 for more plug-in action.