Seen this story of how a group identified the IP addresses of posters on a notorious anonymous economics web forum?

https://www.insidehighered.com/news/faculty-issues/diversity-equity/2023/07/20/study-says-it-found-ip-addresses-anonymous-ejmr

Well here's the original paper. The techniques are pretty jaw-dropping:

https://www.insidehighered.com/sites/default/files/2023-07/ejmr_paper_nber(1).pdf