Talk about money laundering.

An ordinary check made out to person A is bathed in a chemical available at any hardware store. In just a few minutes, it is blank again and made out to person B, -who is a thief.

This process, which has been around for decades, is known as "check washing" among con men, and in an era of high-tech crimes it seems almost quaint.

Except that it's back. Along with other check crimes.

"What we are hearing is that it's a backlash after so much effort made by banks to boost security on their Web sites," said Will Wade, technology editor for trade journal American Banker. "Some of the scammers are going old school with the easier stuff."

U.S. banks lost $711 million because of check fraud in 2005, the most recent year the Federal Reserve studied the matter. But that is only a drop in the bucket.

Losses to individuals and business owners, -many of whom will never realize they have been scammed, -probably push that figure far higher.

It is familiar territory for reformed fraudster Frank Abagnale Jr., whose scams--some involving misdeeds with checks--were so infamous that Steven Spielberg made a film about him, "Catch Me If You Can."

"These people today are doing the same thing I was doing 40 years ago," said Abagnale, now a security consultant and author.

But not all the schemes are stuck in the past. A new fake-check fraud, which often makes use of digital printers and the Internet, has proved to be particularly potent.

The non-profit National Consumers League last year received more complaints about fake checks than any other scam, except those involving online auctions and purchases.

Here's a guide to the workings of two of the more prominent check scams, one retro and the other recent:

-- Check washing

This was one of the hallmarks of Abagnale's former career, and it still is very much alive.

It involves "washing" off the payee and amount written on a check and substituting fraudulent information.

In most cases, the scammer first obtains a legitimate check through a variety of means. It can be one that was placed in a home mailbox as outgoing mail, or one used to innocently pay for services, such as yard work.

If the check is made out in ordinary ballpoint pen, the scammer uses an over-the-counter solvent to get rid of the writing on it, while leaving the bank routing numbers and name and address of the account holder, and fills in new information.

One defense against this type of fraud is the use of a "secure" pen, such as the Uni-ball 207, that dispenses ink impervious to many solvents. It is cheap protection, costing about $2.

If the scam is successfully carried out, and the amount on a washed check is deducted from an account, chances are good that the victim can have the money refunded.