I've recognized two people on here that I know; one which recently attended college with me and another who is incidentally someone I'd rather not see.
However, total between LPSG and the rest of the online space -- I've found SEVERAL people that I know from real life's nude pictures. One particular guy who I've thought was cute for a long time, has a penchant for posting vids of himself and his girlfriend on a website. Bookmarked!