A great research tool that sits within Firefox and can be accessed both on- and offline. Like del.icio.us, Zotero automatically captures citation information from web pages and allows you to add notes, tags and attachments. Unlike del.icio.us it also stores copies of Word and PDF docs, images and other files.
Zotero’s main window consists of three panes. The left pane is your library and holds your collections. This is a repository of all the webpages, files, articles and books you have added.

The middle pane displays all the items in the currently selected collection. It’s also a working area, where you add new items and edit existing ones. Use the New Item button on the top of the middle pane to add a new item, which can be a journal article, webpage, podcast, map or book. The other buttons on the toolbar, allow you to add the currently opened Web page to the collection, take a snapshot of the Web page, create a standalone note or do an advanced search.

In the right hand pane you can add notes (I often cut and paste the first few lines of a webpage in here), attachments and tags to a item. This pane also displays all the bibliographic information about an item such as publisher, edition, date, ISBN, and URL.

Another neat feature of Zotero is that it can detect items within the currently open webpage. For example, in Amazon a book icon will appear on the address bar when you are looking at a book. Clicking on this automatically adds it to Zotero, with all the bibliographic information. This feature works on a large number of other sites.

The only drawback with Zotero at the moment is that your entire library is stored on a single machine so, unlike del.icio.us, it can’t be accessed from anywhere.

Download Zotero from here.