"But here's why some people probably don't like personalization: It's invisible. There is nothing on the results page that tells you whether your results are personalized or not." Sorry, this is just not the case: we do provide indication on Google's search results page for personalized results.
Did you know that you can easily find unprotected, secrete files on the internet by simply doing some Google Searches on web directories that do not have a default index file or have set file and folder permissions incorrectly? With these directories, you can find some interesting and unprotected files like videos, swf files and music.