An example:
access.log.38.gz:96.x.x.x - - [09/Jan/2015:02:24:52 +0000] "GET /r/config/server/top-menus HTTP/1.1" 200 626 T=0s "https://gerrit.wikimedia.org/r/#/q/owner:%22Chasemp+%253Cchasemp%254<foo>.com%253E%22,n,z" "Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko"
We have this kind of stuff back to 2014. In some cases it could be construed as 'who I am/What I care about/Where I am from'.