When Paypal, which is owned by eBay, learned that spammers were using its name, they put a digital signature on their e-mails and asked providers like Yahoo and Google to block any e-mail purporting to come from them which did not have that signature.

"We know how many they throw away and it's approximately speaking about 10 million a month," said Michael Barrett, Paypal's chief information security officer. "If the consumer never sees the e-mail in the first place then it's hard for them to get victimized."

"Phishing was not just impacting consumers, in terms of general loss, it was impacting their view of the safety of the Internet and that it was indirectly damaging our brand," added Barrett.

Security experts say they are seeing more and more shifts from outright fraud, where the victim will hand over their money, to the use of malware, basically malicious software which, among other things, collects passwords and credit card numbers for thieves.

Those will then be sold on the underground market," said David Marcus, a threat research expert at McAfee computer security firm.

The person purchasing the passwords and card numbers will use that information to make purchases, get cash or create fake identities.

The Federal Bureau of Investigation, working with police in the United Kingdom, Turkey and Germany, shut down one such online forum called Dark Market in October 2008 which, at its peak, had more than 2,500 registered members, according an FBI press release issued at the time.

But experts agreed that they didn't expect the problem to go away anytime soon, and that more people out of work could well mean more people like to fall for scams.

Marcus said many of the scams were nothing more than the digital equivalent of confidence tricks, although on a massive scale that can net some scammers more than $100,000 a month.

"These things only have to be 2 percent successful," he said. "Those campaigns are sent out to tens of millions of people at the same time.