Late last year a grumpy gate agent at IAD told me that United would be getting rid of same-day standby soon, because too many people were gaming the system by buying a cheap late flight and showing up at the airport to take the expensive early one.

"That's ridiculous," I figured. "People take on a lot of risk by standing by because they aren't guaranteed a seat, and it wouldn't make sense to punish that with a fee like US Airways does. Plus, this is one of the awesome features that really makes United stand out and makes me want to recommend the airline to my friends." But I didn't say anything out loud -- I just kind of nodded and smiled. I guess she was right!