Quote from: cbeast on December 02, 2011, 11:13:35 PM

The city is filled with stories like this. Some are even true.
Sally is paid by her boss in Bitcoins. Her employer automatically takes out taxes from her registered Bitcoin address. After paying her bills to registered business Bitcoin addresses she decides to take her remaining salary and go out. Sally calls an escort service and pays their public address. She then meets Lance for a night of frolic. While she is in the shower the pizza arrives at the motel room. She tells Lance to pay the pizza guy Bill with her card. Her card is designed to only accept registered addresses. Lance is disappointed because he was hoping he could buy drugs from Bill with her card too, but ended up payiing for them with a physical Bitcoin and was unable to get change. Bill pocketed his profit thinking "stupid junkie."

Bill is caught by police buying more drugs to sell. They ask him where he got a whole Bitcoin. Bill tells him that it was a tip from a nice lady. Police check his employer records and find his last delivery. They investigate and find Sally barely alive. They rush her to the hospital. Meanwhile Lance was trying to pawn her jewelry. The first pawn shop wouldn't take his items because Lance refused to give them his registered Bitcoin address. They learned their lesson when an undercover cop pawned jewelry and offered to take half the money if they would use an unregistered address. The next pawn shop would register an address for him if he would wait 10 minutes for the transaction to verify. Lance was desperate for another fix so he agreed to wait. Police picked up the unregistered transaction by the pawn shop IP address and intercepted the perp. The escort was then investigated, but the police chief cleared them of any wrongdoing. Sally later went on Oprah with a book she wrote about how Bitcoin saved her life.

Amazing!

But: this all makes the bold assumption you can absolutely tie an address and specific Bitcoins with an individual or entity.
It won't happen, I can assure you. (Some hints: connecting through Tor; building OpenTransaction overlay upon bitcoin > exchanging blind tokens, etc)