F1 is a browser extension by Mozilla Labs is the simplest way to share, spread, and save interesting web-pages via your social networks such as Facebook, Twitter and email with Gmail. These three services were chosen based on their popularity and OAuth implementation.
The F1 button (not the F1 key on the keyboard), which works in Firefox 3.6 and 4.0, sits in the top right corner of your browser, next to the search bar. The first time you use it, you need to authorize any (or all) of the three services. After that, you simply hit the F1 button, select a sharing service, and hit share.
F1 button automatically shortens URLs using bit.ly and then inserts the shortened URL into your tweet, making the whole process seamless.
There are other options, such as AddThis and Shareaholic, that already work to tidy up the mess of share buttons. But, F1 is faster and more convenient and this is just the beginning! While it only supports Facebook, Twitter and Gmail for now, Mozilla Labs talks about an API that will allow social sites to hook into Firefox; in theory, F1 could support any and all sharing services, all from within the browser.