Zotero is a FREE Firefox add-on that acts as an online/virtual file cabinet for the articles and citations you collect in the course of your research. Not only can you file materials, you can store them in "the cloud" so you can access them anywhere. Finally, Zotero can insert parenthetical references as you write your paper (using a Word or Open Office add-on) AND instantly create a bibliography in your desired format when you are ready for your works cited list.