EWeek has an interesting article on the Secret Service's Operation Rolling Stone, the fed's latest effort to fight cyber-crimes.
One of the things that the article highlights is that it's not just high-tech investigative techniques that crack the case: often, it's the crook's own stupidity that helps the investigators.
For instance, the feds convinced one suspect to be paid by Western Union rather than PayPal, tagging them for wire fraud. And another suspect provided his real name for payment.
"... another defendant who went through great pains to keep his credit card creation company efforts secret, but proceeded to buy much of his equipment publicly on eBay—using the same name he used for deceptions. Correction: He changed one letter. (Second note to cyber-bandits in training: This is not a job for the lazy.)"