Any of the 263 million Yahoo Mail users who were antsy for change now have something they can sink their teeth into.

The first real fruits of Yahoo's $350 million acquisition of Zimbra are becoming apparent with the release Thursday of the Yahoo Zimbra Desktop. The e-mail software, available as a free download, works when the user is offline, and it offers options for basic online word processing and spreadsheets, task management, and file storage.

Zimbra Desktop's e-mail interface should be familiar to users of either Outlook or Yahoo Mail.

Zimbra Desktop's e-mail interface should be familiar to users of either Outlook or Yahoo Mail. (Click for larger version.)

(Credit: CNET News)

Zimbra Desktop means that Yahoo beat out Google in the race to provide e-mail that also works offline, but it took a different approach to get there. Google looks to be adding offline access through the open-source Gears project, a plug-in that augments a Web browser's abilities.

But Zimbra Desktop, while using browser interface technology called Ajax that can give Web browsers an elaborate interface, actually runs as a standalone application. It employs Java software to store data locally, and it's a hefty download--38MB for Windows, 34MB for Mac OS X, and 44MB for Linux.

Yahoo has formed a new group focusing on cloud computing, in which services available on the Internet substitute for local applications. But until the day when a reliable, fast Internet connection is available anywhere, offline access to applications is a significant feature.

Webmail is a compelling facet of cloud computing, letting people reach their e-mail from any number of computers or mobile devices. But from a user's point of view, Zimbra Desktop's approach--a downloadable application that doesn't run in a browser--is actually more like traditional e-mail client software such as Microsoft Outlook or Mozilla Thunderbird.

Zimbra Desktop gives access to basic word-processing abilities, with documents stored online.

Zimbra Desktop gives access to basic word-processing abilities, with documents stored online. (Click to enlarge.)

(Credit: CNET News)

After many months of quiet integration, Zimbra's ascent within Yahoo has been apparent. As part of a major reorganization in June, Zimbra leader Scott Dietzen was named to run all of Yahoo's messaging and communication work.

The software can be used to connect to Yahoo Mail and also to other accounts such as AOL or Gmail that support remote access via POP (Post Office Protocol) or the newer IMAP (Internet Message Access Protocol).

I had no trouble installing, configuring, and running Zimbra Desktop to send and receive e-mail. As with Yahoo's Webmail interface, it mirrors Microsoft Outlook's look and keyboard shortcuts.

However, it's not perfect. It didn't seem connected to my Yahoo address book for contacts or calendar for events.