Mozilla Thunderbird is the safe, fast email client that’s easy to use. It has lots of great features including quick message search, customizable views, support for IMAP/POP, RSS support and more.
The portable version leaves no personal information behind on the machine you run it on, so you can take your email and address book in your USB drives wherever you go.
The 3.0 Beta 3 release will install alongside a Mozilla Thunderbird, Portable Edition installation by default in a Thunderbird Portable Test directory.
If you’re looking for the stable version, please go to this page.