On "On the economics of anonymity"

Since posting "On the economics of anonymity", I ran across a paper of the same title. Being an actual research paper, it goes into considerably more depth than my brief take. Some of the high points:

• An anonymity service can be viewed as a "public good." A public good is something that everyone can use without diminishing someone else's ability to use it. Street lights are a classic example.
  
• In most public good scenarios, "free-riding" (using the good without paying for it) is a problem. In anonymity systems, free riders can also be good, since they provide cover traffic.
  
• You're more anonymous as a node than as a free-riding user.
• Parties that value anonymity highly have good reason to become nodes, despite the higher costs. Everyone else might as well just use the system.
• More nodes means less traffic per node, means less anonymity.
  
• It appears difficult to set up an anonymity system that everyone will have an incentive to use, particularly if you're starting from scratch.

For more details, please see the paper itself. It, and many other goodies on anonymity, are available on Freehaven's excellent Selected Papers in Anonymity.