One of the most appreciated e-mail clients in existence, Mozilla's Thunderbird, also comes in a portable flavor, so its users can enjoy the same functionality even when they are not in from of their home computer.
Runnable from an external storage device, Portable Thunderbird provides all the great features that can be found in the desktop installer version. The mail management and contact organizing characteristics, alongside chat and news reader abilities make this software the preferred client for many users.
The e-mails can be sent to custom folders, saved or exported in various formats in batches and the great thing about Portable Thunderbird is that you can do this for several accounts from the same friendly interface.
The powerful filtering and search features will help you identify specific messages or information contained in an e-mail in just a few seconds. For each mail you have in the Inbox or inside another folder you can assign tags, according to their importance. Even the tags are customizable, meaning that you can create new ones, of your own, right on the spot.
Another sought after characteristic that is present in Portable Thunderbird is the extensibility of the program. This means that you can enhance the functions and capabilities of the e-mail client by enlisting the help of dedicated add-ons.
The extensive configurations available for each account listed in the e-mail client, as well as the rich 'Options' menu, offer the user the possibility to modify the utility's functioning parameters in great detail. Security is taken very seriously and you can integrate the protection offered by the installed antivirus, set junk and scam e-mail parameters and protect passwords with strong encryption.
To conclude, Portable Thunderbird is definitely one of the best choice you can make if you're looking for a powerful, yet easy to use e-mail client. Packing a lot of features, yet allowing many customizations, this e-mail client deserves a place in anyone's utility belt.

What's New in This Release:
· NEW: Message threads can now be ignored or watched
· NEW: Emails can now be sent to IDN based email addresses
· NEW: Zoom functionality is now available in the compose window
· CHANGED: In the Compose window, ctrl/cmd + and ctrl/cmd - now change the zoom setting rather than the font size
· CHANGED: In Twitter, replying to a tweet now replies to all users, just like on the Twitter website
· FIXED: Interactions in the filter list dialogs have been improved
· FIXED: In Chat user nicknames are now highlighted when mentioned
· FIXED: In IRC, long messages will now be sent in multiple parts instead of being cut off
Various security fixes:
· MFSA 2013-92 GC hazard with default compartments and frame chain restoration
· MFSA 2013-91 User-defined properties on DOM proxies get the wrong "this" object
· MFSA 2013-90 Memory corruption involving scrolling
· MFSA 2013-89 Buffer overflow with multi-column, lists, and floats
· MFSA 2013-88 compartment mismatch re-attaching XBL-backed nodes
· MFSA 2013-85 Uninitialized data i...

Users are advised to pay attention while installing this ad-supported application:
· Displays ad banners or other types of advertising material during its runtime