Silk Road is a peer-to-peer commerce website like eBay, with a few important differences: it's only accessible through the anonymous network Tor, purchases can only be made with the digital currency Bitcoin, and much of the trade is in drugs. In a revealing piece for Gawker, Adrian Chen explored the underground site. It's worth reading the whole piece, but here's a key snippet:
Sellers feel comfortable openly trading hardcore drugs because the real identities of those involved in Silk Road transactions are utterly obscured. If the authorities wanted to ID Silk Road's users with computer forensics, they'd have nowhere to look. TOR masks a user's tracks on the site. The site urges sellers to "creatively disguise" their shipments and vacuum seal any drugs that could be detected through smell. As for transactions, Silk Road doesn't accept credit cards, PayPal , or any other form of payment that can be traced or blocked. The only money good here is Bitcoins.
Bitcoins have been called a "crypto-currency," the online equivalent of a brown paper bag of cash. Bitcoins are a peer-to-peer currency, not issued by banks or governments, but created and regulated by a network of other bitcoin holders' computers. (The name "Bitcoin" is derived from the pioneering file-sharing technology Bittorrent.) They are purportedly untraceable and have been championed by cyberpunks, libertarians and anarchists who dream of a distributed digital economy outside the law, one where money flows across borders as free as bits.
A member of Bitcoin's dev team emailed to correct Chen, saying that Bitcoin are not untraceable. Jeff Garzik notes:
If you visit the bitcoin wiki page on anonymity --While the Bitcoin technology can support[link] strong anonymity,
https://en.bitcoin.it/wiki/Anonymity -- the first sentence is
the current implementation is usually not very anonymous.
With bitcoin, every transaction is written to a globally public log, and the lineage of each coin is fully traceable from transaction to transaction. Thus, /transaction flow/ is easily visible to well-known network analysis techniques, already employed in the field by FBI/NSA/CIA/etc. to detect suspicious money flows and "chatter." With Gavin, bitcoin lead developer, speaking at a CIA conference this month, it is not a stretch to surmise that the CIA likely already classifies bitcoin as open source intelligence (no pun intended).
Further, if Silk Road truly permits deposits on their site, that makes it even easier for law enforcement to locate the "hub" of transactions.
Attempting major illicit transactions with bitcoin, given existing statistical analysis techniques deployed in the field by law enforcement, is pretty damned dumb. :)