Rather than brass knuckles and baseball bats, the weapons of choice for these digital extortionists are thousands of computers. They use them to launch coordinated attacks that knock targeted websites off-line for days, or even weeks, at a time.
The shakedowns generate millions of dollars. Many Internet operators would rather pay protection money than risk even greater losses if their websites go down.
After more than a year perfecting their techniques on gambling and pornographic websites, the gangs are starting to turn their talents to mainstream e-commerce operations.
"It's pretty much a daily occurrence that one of our customers is under attack, and the sophistication of the attacks is getting better," said Ken Silva, a vice president at VeriSign Inc., the company that maintains the ".com" and ".net" domain name servers and provides security to many firms.