The Feds go subpoena-fishing on Reddit: http://www.wired.com/2015/03/dhs-reddit-dark-web-drug-forum/

Notable parts (emphasis mine):

Earlier this month, a Baltimore Department of Homeland Security (DHS) Immigration and Customs Enforcement agent sent a subpoena to Reddit demanding that the site turn over a collection of personal data about five users of the r/darknetmarkets forum. ... The subpoena’s five targets are NSWGreat, a user who had claimed to be an Evolution staffer; three other users named z-l, Deepthroat and Evosmith who boasted on Reddit that they were tracking Evolution’s administrators or identifying details about them; and Gwern Branwen, a well-known security researcher, writer and moderator of the darknetmarkets forum. It’s Branwen who has now publicly revealed the subpoena’s existence to WIRED.