The Feynman Files. For the first time, FBI records for Dr Richard Feynman have been released to the public. They document the Bureau's apparent obsession in the 1950's with outing him as a communist sympathizer, and include notations from several background checks as well as interviews with his colleagues, friends and acquaintances.
In December 1974, New York Times reporter Seymour Hersh's front-page account (paywall) of the CIA's MK-ULTRA program documented their illegal domestic intelligence operations against the antiwar movement and other dissident groups in the United States. The article eventually prompted investigations by the Rockefeller Commission and the Church and Pike committees. "There have been other reports on the CIA's doping of civilians, but they have mostly dished about activities in New York City. Accounts of what actually occurred in San Francisco have been sparse and sporadic. But newly declassified CIA records, recent interviews, and a personal diary of [George H. White,] an operative at Stanford Special Collections shed more light on the breadth of the San Francisco operation." SF Weekly: "Operation Midnight Climax: How the CIA doped San Francisco citizens with LSD." MK-ULTRA: Previously on Metafilter. (Via)
When journalists from Radar Magazine interview John Young of Cryptome.org, Young suspects he is actually being double-crossed by MI6 agents.
The NSA Bibliographies The NSA internally publishes thousands of papers every year, on every topic from spycraft to cryptography to physics & aliens (no, really!). Each year the titles of these papers gets indexed & those indexes are also published internally. The Memory Hole has made a successful FOIA request for a large number of these, spanning almost 50 years. We don't get to see the actual papers, but just the titles are fascinating - including such page turners as "Computer Virus Infections: Is NSA Vulnerable?", "KAL 007 Shootdown: A View from [redacted]", "NSA in the Cyberpunk Future", "Telephone Codes and Safe Combinations: A Deadly Duo", "Coupon Collecting and Cryptology", "Cranks, Nuts, and Screwballs" & my personal favorite, "Key to the Extraterrestrial Messages". When you're done browsing the titles, there's a sample form you can use to request some of the documents yourself!