Or if you know to apply for business cards without having a real business.

It's not hard with Citi or Amex. Just answer the questions for the minimum size of business you could possibly have (say, selling items on eBay, which I have legitimately done in the past, though not in recent years, or by any kind of consulting), and when Amex asks you your expected spend, give the minimum spend divided by the number of month you need to the minimum spend in .

(Chase can be harder, especially if you can't resist the temptation to call when they ask you to call. They can grill you left and right about your business. Whereas often if you don't call back when they ask you to, if you just wait a while they're likely to approve you anyway. So that call they're asking you to make is just a ruse for them to find an excuse to deny you! )