I haven't seen this mentioned before: Google Docs/Drive now has a rudimentary research tool that theoretically makes it easier to insert links, citations and maps into documents.

https://support.google.com/docs/bin/answer.py?hl=en&answer=2481802&p=documents_research

http://www.gizbot.com/how-to/how-to-use-research-tool-on-google-drive

http://www.gizbot.com/how-to/how-to-use-research-tool-on-google-drive