RefWorks: RefWorks is an online tool that is free to all BU users. It allows you to store and organize citations, and generate bibliographies within a matter of seconds. Use RefWorks if you want to use a tool that works seamlessly with databases such as CINAHL and PsycInfo. It works well with PubMed, but requires an extra step.
Mendeley: An free, online tool for all users. Similar to RefWorks, and it works seamlessly with PubMed.
abstrackr : A free, online application from Brown University that facilitates screening of citations by multiple reviewers.