 And while passengers used to have to make their final payment two months before a sailing, some cruise lines are asking for that three or four months ahead of time, giving them use of your money for longer. However, some cruise lines will give you a 5% to 20% discount if you pay in full up front, which, given what your money earns or doesn't earn in a bank these days, isn't a bad deal. Tomorrow, I'll tell you more ways cruise lines are making money quietly. You can find info and more at rudymaxa.com.