Business Expenses and travelling. Other than that I use my B of A debit or whatever they give me with 0%.

They have been fantastic with dispute resolution. United (the world's worst airline) diverted my flight from IAD to PWM when we were 15 minutes out for no good reason (CFO's a pilot, sitting at the airport... they claimed fog) They shut off the lights at the airport on me back in DC, so AE took care of my bill at the Marriott (Hey, it was the closest one) and then reversed the charges on United, since three flights the next day were cancelled, and I hopped a ride home with a US Senator who lives in my neighborhood on another airline.