AllPeers

Allpeers is a Firefox browser plugin that enables the private sharing of files with groups and individuals. The plugin is available for Windows, OS X and Linux, and the installation process is fairly straightforward. After restarting Firefox you can get access to a left sidebar that lists your friends and family in a instant messenger-style list. Files can be shared with one individual, a selected group or everyone on your contact list. Download the extension (for the Firefox web browser only) at http://www.allpeers.com/

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