Evernote is a must have and this extension really is vital Rated 4 out of 5 stars
Evernote has been a staple of mine for years, I have used it from version 2 way back. This extension really helps integrate it into Firefox and is vital for web clipping. Evernote features cross platform integration too, Windows, Mac, Android iDevices, all can access the SAME online notes and cache the notes offline. As Jerry Pournelle often says; Highly recommended!
Please hurry and get the new version for FF 8 ready! Even editing the extensions RDF file internally to a higher version doesn't allow it to function. I miss it!