Why is your Google not my Google?
Students often come to the Reference Desk having tried a preliminary search on Google. They are astounded to find that the Librarians can find relevant materials using the same search terms they tried on their own without getting any useful results.
Take nine minutes and watch this TED video presentation from earlier this year. Google, Bing, Facebook, et al., are filtering your results. And you don't know it. Until now, that is.
Thanks to Sue Lyons at Rutgers-Newark for pointing this out.