Yesterday at work my co-worker told me about a time she went to the library. A line had formed to enter because a security guard was checking bags as people came in. As she waited, my co-worker became aware of an unpleasant odor. It turned out that the guy in front of her was holding something brown in his hands. The security guard took a look and waved him into the library. "It's not that he was homeless and carrying shit into the library that bothered me," she said. "I'd be upset if he was in a full suit and worked at Lehman Brothers and was holding shit."

"Yeah, those collateralized debt obligations!" I laughed. She stared at me. "You know, collateralized debt obligations?" Blank look. "The things that the investment banks used to package mortgages that tanked the economy?" She nodded. "Well, they were essentially piles of shit so I thought you were making a hilarious joke about CDOs."

Once in a while, it is good to remember that I live on my own little public policy/finance planet. I am such a dork. But I still think that is a funny joke.