I can see how desperate people with bad credit would be willing to try this gambit -- even though it comes at a steep cost. Oh yes, to get attached to someone with good seasoned credit, it will cost Mr. Desperate anywhere from $700 to $2,000 -- up front -- depending on the size of the credit line you access. Then again, as one Web site claims: "A higher credit score is priceless!" But what could possibly be the appeal to someone with good credit -- and thus presumably with a working set of brains? As P.T. Barnum said, "There's a sucker born every minute!" The online advertisements promise that people with good credit can "Earn up to $10,000 a month or MORE." For each additional authorized user on your card, you'll be paid about $100 to $150. They won't tell you exactly how much until they "see your credit." In case the math escapes you, if you decide to sign up for this insane idea of "sharing your good credit," you're not getting paid nearly as much as the company collects from the deadbeat who wants to borrow your credit. The difference is the huge profit these matchmakers get. Matching desperate borrowers and greedy cardholders could be a big business. One site brags that it has over $1 million in "aged credit accounts" -- just waiting to add you as a user. Click on the link for "credit investors" (those with credit to spare) and they remind you that many cards will let you have at least 10 additional signers, and some card issuer allow 99 people to be authorized users.