Firefox only: Somewhere between web-based email and a standalone desktop client there's Simple Mail, a Firefox extension that embeds an email client right inside a Firefox tab. Manage all your messages in Simple Mail, which can notify you of new incoming messages at a rate you define for any number of POP or IMAP email accounts. Simple Mail lists your messages in a familiar three-paned view where you can read, compose, and send messages, as well as maintain an address book. I had trouble getting Simple Mail to work with Gmail and IMAP in Firefox 3 on the Mac, but all went well in Firefox 2/Windows, so Mac users, proceed with caution. Simple Mail is missing features you'd expect in a full-blown client—in fact, I couldn't get it to see the folders on Gmail's IMAP server. However, it does give you that desktop feel without having to run or switch to a separate application. Simple Mail is a free download for Firefox only. Thanks, Masa!
Simple Mail [Firefox Add-ons]
Firefox 3.5 works with whatever mail client is the default on your system. However, we recommend Mozilla Thunderbird, our next-generation email client and the perfect complement to Firefox.
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