I realize that bitcoin is pseudonymous vs. anonymous and that precautions must be taken, but I came across two easy-to-find web pages that should serve as a harbinger of how
law enforcement will utilize bitcoin data should it attain critical mass:
1.
http://buybitcoins.com/ Look at the Google maps from the crooks real (or proxy) servers. Now, this company lost over $2,000 in fraudulent cc transactions which is wrong, but the larger point is that a shocking amount of information is available from sloppy users. Consider if this were political prisoners from Tibet, Wikileaks benefactors, or simply international business people wishing to keep an income stream private from confiscatory taxation authorities;
2.
http://theymos.ath.cx:64150/bbe/ This is the Block Explorer brilliantly assembled by 'theymos'. I almost fell out of my chair when I imagined law enforcement each having Block Explorer running as their home page. Theymos should receive many donations (from governments, I suspect).
The implications are obvious. In the trade-off to cryptographically address the double-spend issue, Bitcoin has left a transactional trail of valuable data which can be beneficial to anyone attempting to piece together a profile. As Bitcoin matures, more services such as mybitcoin.com, bitcoin banks, and bitcoin mixers will be routine practice because otherwise the casual (or novice) user will be unaware of the trail that could easily lead to physical and geographical identity. The privacy features of a $100 bill or a 500-euro note should be the minimum standard of financial and transactional privacy.