Zotero
Open Source
Zotero is a powerful, easy-to-use research tool that helps you gather, organize, and analyze sources and then share the results of your research.
Paperpile
Commercial
Paperpile is a web-based reference management software, with special emphasis on integration with Google Docs and Google Scholar.
Mindomo
Freemium
Mindomo is an online mind map Software where users can create, view and share mind maps in their browser.
