ACLU challenges legality of NSA's spying, and here's what your phone metadata reveals

The American Civil Liberties Union is challenging the National Security Agency's vast spying of Americans' phone calling data [PDF]. This week, the ACLU asked the court to issue a preliminary injunction to halt the surveillance program so that its legality can be litigated. The program reportedly collects only metadata about our phone calls, not the conversations themselves, but your metadata can reveal a lot about you, as Timothy B. Lee explains in this WaPo item. And, lest we forget: all of this was brought to you by Edward Snowden.