There was the guy a year or so ago who outed his socks, but I don’t think that fits what Quasi is after.
However, I believe the Mods do identify a number of posters trying to come back under different names and the gavel drops. I don’t know if you would call that a sock.
Most people come to message boards to post about topics that interest them. In order to escape detection for any great length of time, a returnee (at least one who had been here long enough to establish definite behavior patterns) would have to avoid talking about their favorite subjects, so what would be the point? And returnees may sometimes be identified by idiosyncrasies of posting style that they are probably not even aware of.
Let’s not forget mass media. When more and more characters on the TV and movie screens are stated to be or implied to be of the SP orientation, you can bet that will help change mainstream society’s perceptions.
It wouldn’t hurt to have a new term, since there is so much instant recoil at sock puppets. How about happies?
“Deja Vu” – sort of. In the days before the web, there were APAs, such as Interlac. {See wikipedia; technical problems here} A running gag, just before I joined, was that member X was just a figment of Y’s imagination. Finally, someone claimed that all of membership subset G was just the imagination of a particular popular member, H.
That individual had a uniquely “colorful” way of expressing his opinion of the fad.
He said that reading such jokes was like masturbating with a handful of sand.
Although that is the classic meaning of “sock puppet,” it actually happens fairly rarely on this board, and is comparatively easy to detect (mostly because people who do such things are usually as crazy as loons).
The far more common type of sock here is a bannee who tries to return under another name. Sometimes posters create a second name in order to troll or express unpopular opinions while leaving the reputation of their original name intact.