People with shaky credit can fall prey to shady credit card deals.
Some are downright dishonest, some are offering credit cards that really don't stand up when you put a spotlight on them.
And if you do sign up, be sure the company offering the deal is the right one (i.e., do they come directly from the card issuer?). If not, contact the card company to be sure the cards are authorized.
A little research could save you BIG on interest.