Tor is vulnerably to sybil attacks. How are you dealing with it?
It's time to realize that Tor is vulnerable to sybil attacks. Adversaries, such as NSA and GCHQ can make enough Tor relays to fully deanonymize everybody using Tor with high probability. The base of the Tor security is the idea that an adversary cannot control more than one relay in a circuit, it is true if the relays are intended to protect the owner of the networks and are controlled mostly by the owner of the network, but it is not true if your goal is to protect anyone and adversary is able to create a lot of malicious nodes contributing to your network.
How are you dealing with this? Don't say 'sybilhunter', it's easy to bypass it by fairly creating relays as anyone creates them: just order the employees to lend enough VPSes in different datacenters and install Tor on them. Don't say 'it costs too much', NSA has huge budgets.
How are you dealing with this?