On LessWrong I use my surname and the first two letters of my lastname as nickname. That means, if someone Google's my name he won't find my LessWrong posts. If someone however knows me and reads LessWrong I think he can deduce my identity. When possible I also use an avatar image of myself to make it easier to recognise me. I'm doing Quantified Self community building and multiple people who are into Quantified Self participate on LessWrong. I might say things on LessWrong that offend somebody but I think that people here are generally able to accept people with different viewpoints and won't hold something I write here against me outside of LessWrong. My Quantified Self online identity is linked via speaking engagments and mainstream media interviews with my real life. Other links between my online identity and offline identity are found in facebook. A bunch of my facebook friends come from online sources. I was roommates for a few months with a guy where the first contact was online and where facebook was the medium that allowed me to know that he moved to my city and needed a place to live. With another good friend of mine it was similar. We had minimal online contact. Then we became facebook friends. In physical space we meet the first time accidently in a toastmasters club and were surprised that we are facebook friends. Today he's one of my best friends. Especially if you have interests that aren't shared by most people turning online relationships with people who share your interests into real world interactions is very worthwhile. The less walls that you build around yourself with privacy protections, the more likely you are to interact with people you know online in real life. So far I don't know of a relationship that I lost because of something that I wrote online. If something I write online however offends someone I know offline to the extend that the person wants to end the relationship, we probably don't have much shared interests anyway. I wan

It's hard to judge. When I started seriously participating in stuff online, I kept heavily pseudonymous so I could disavow it later (I was still growing up) and out of interest in crypto & security issues. This came in handy when I earned some enemies on Wikipedia who sought to 'out' me; one group went so far as to call up universities looking for info on me in order to harass me and in the best-case scenario, get me fired from a job. Naturally, they failed. More recently, I learned of death threats; I believe the threat to be very minimal, but it's still not a particularly happy thought. The point being that when I started, I didn't seriously expect stalkers and threats, but if I had started 'public', I didn't have the option to retract all the relevant privacy info.