Shelfster is a free site that allows you to bookmark and annotate websites while researching. You can create a document, edit it with a simple drag/drop of links, or type in your document as well. Then save it online (as part of the free account you create) or download it as a PDF.
Shelfster also has an iPad and iPhone app.
Classroom Integration Ideas:
Shelster can help students organize their internet research. Shelfster will soon integrate with Google Docs, which could allow students to share and peer edit their research.