With identity theft an ever-growingthreat, many consumer experts are warningthat shredding preapproved creditcard offers that show up in your mailboxmay not be good enough. They suggestcutting off the flow of credit card mailingsat the source. You can do that by callingthe Consumer Data Industry Associationat 888-5-OPTOUT. This one phone calllets you tell the big three credit reportingagencies (Experian, TransUnion, andEquifax) that you don't want your nameand address sold to credit card companies.You can also block about 90% of alljunk mail through the Direct MarketingAssociation (DMA; www.dmaconsumers.org). Registering at the site will put youon the DMA's do-not-mail list for 5 yearsor until you move. DMA membershave pledged to honor the do-not-maillist, but nonmembers can ignore it.