Back in Friendster's hey day, it had the notable "feature" of letting you see who's viewed your profile. Maybe Myspace had something similar, but this seemed thoroughly baked into the UX. I learned later that you could disable "exposing" yourself, at the cost of not seeing who's viewed your own profile.<p>After a long browsing sesh of flipping through friends and friends of friends profiles, I received a message from a girl who jokingly called me out via DM for viewing her profile and I responded in kind. We've been happily married 13 years now :)