[sundarurfriend]

/r/EqualAttraction seems to be it (I just searched for 'similar attractiveness' on reddit, was the third or fourth result). Now my problem is I don't know any of the celebrities they are naming, so I'll have to google around to see if I agree with the commenters.

[hairofadog]

I'm pretty sure that was it – when I saw it years ago, there were a few posts that were pretty remarkable, in that somebody "average" looking had uploaded a picture, and someone else would upload a pretty good (non-celeb) match, and in most cases the op would say, "Oh, that's way better than I thought!"

Looking at it now, however, it seems like it's mostly a "what celeb do I vaguely resemble" thread, which isn't nearly as interesting.