First, for those who don't know what Tor is: https://www.torproject.org/
"Tor is free software and an open network that helps you defend against a form of network surveillance that threatens personal freedom and privacy, confidential business activities and relationships, and state security known as traffic analysis."
That said, I saw this Bruce Schneier's Crypto-Gram newsletter. Basically a list of tips for improving your Tor anonymity game. Some is common sense: Tor benefits don't amount to a hill of beans if you go about bragging that you use it. Other tips are considerably more technical and fine grained for you gearheads out there:
Cryptome: Tor Operations Security
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