A very mind-blowing reality check article from ZeroHedge about how Google and Facebook store every single little thing you do online or with your cell phone.
The beginning of the article:
Or simply go to this kind gentleman's (Dylan Curran) Twitter post on the matter.
These are only the first 8; there are 30 items on his list!
There are a bunch of links to both Google and Facebook services so you can check the personal goods they have about you. I'd strongly suggest you have a look...and you will get freaked out for sure.