I just filled up my car with gas. It cost me a twenty dollar bill to completely fill it up. An entire twenty dollar bill. A $20 bought me gas - not gas + soda + pocket money, not gas + lunch, just gas. Youch.
Full disclosure: It was very empty. I don't know if I've ever put that much gas into it - the amount of gas I put in disproved my previous theories about how big my tank was. (Hey, I bought it used!)