Robin Good: Mendeley is a cross-platform research tool, which can help you tap into a vast online library of over 30 academic paper databases, while helping you "curate" your own library of references, bibliographies and reference documents.
From the official site: Mendeley is a free reference manager and academic social network that can help you organize your research, collaborate with others online, and discover the latest research available.
-> Generate citations and bibliographies in Microsoft Word, OpenOffice, and LaTeX.
-> Open PDFs and capture your thoughts through sticky notes and highlights.
-> Import and organize PDFs from your computer, EndNote™, Papers or Zotero.
-> Collaborate with colleagues and securely share your papers, notes and annotations.
-> Access your papers on the web, iPhone or iPad.
-> Discover papers, people and public groups.
Compare with other research tools: http://www.mendeley.com/compare-mendeley/
Download: http://www.mendeley.com/download-mendeley-desktop/ (available for Mac, PC, Linux and iOS)
Video tutorials: http://www.mendeley.com/videos-tutorials/
Find out more: http://www.mendeley.com/