I recommend you to visit http://webkay.robinlinus.com/ since it make you know how much, how easy and how often are you sharing information about yourself via your browser. Thank your Robin for such an easy way to check what we share over the Internet, unconsciously?
Few time ago I was reading Dan Gillmore in Medium and it revamped my preference for FOOS.
Since I’m running a Cyanogen OS in my smartphone I’ve notice that many common apps asks permission for reading my whole contact list, SMS database or access constantly to my geolocalization. I’ve also realized that my normal browsing is shared among system browser and some apps, so if you wanna avoid unsolicited advertising you have to choose private browsing by default.
So please, visit webkay from Robin and, at least, you will know what permissions are granted in your browser by default. Your privacy matters, it’s all about you, finally.