infoRSS is a lightweight, non intrusive, RSS, ATOM, NNTP and HTML headlines reader for Firefox, Mozilla, Netscape and thunderbird, designed by Didier Ernotte. The extension installs a small icon (looks like an earth) in the status bar. The headlines are displayed in the beside this icon in the status bar or in a separate bar (top or bottom of the screen). The interface is very simple to use: drag and drop new url of feed onto the extension icon to add a new feed or click on the extension icon to select a specific feed to read. The feeds can be grouped to allow multi feed fetch and filter can be used to limit the number of headlines.
It has been tested with Firefox, Mozilla, Seamonkey, Thunderbird, Flock.
Download: infoRSS 1.1.5