Ask HN: Identifying The Anonymous User

Hello Hacker News, it's been a long time since I've asked you guys something and I figured this place was the best place to ask this question:

What are the best or most efficient method to identifying a user without the use of accounts, destroying privacy, or demolishing anonymity?

If the question is too hard, how about if you're just limited to no accounts?

EDIT: I should have specified "Anonymous in the way that 4chan users are anonymous to each other."

EDIT2: The thing that got me thinking about it was this https://panopticlick.eff.org/