I found a pdf copy of The Gulag Archipelago online and started reading it earlier this week. Fascinating material. Aleksandr (I can't spell his last name) used accounts from 227 former prisoners to pen this rather extensive archive.
Even if you can't imagine reading the whole thing (it's a daunting task), I'd urge you to check out the first chapter on the Arrest. Objectively it reads like a Mel Brooks movie without the corny jokes. The Cheka just took people for any reason. AS's little examples end up being almost humorous in the ridiculousness of it all.
Plus it's a good read to enlighten yourself about the specifics of what happened in the Soviet Union to make it the Soviet Union. This Chernobyl show on HBO had me jonesing to know more about the dumbasses of the USSR.
anyway, just a quick plug. it's good stuff.