I had a great experience with a ticket counter supervisor in BOS that stuck with me from a number of years ago. I was supposed to be flying on an early morning BOS-DFW flight. However, this was in 2007 (or 2008) when DFW was seeing big weather/rain just about every day in June/July and a lot of passengers were stranded.

When we made our way up to the counter to find out that our flight was cancelled, the GA offered us the option to stay in BOS for the day or go anywhere else in the US for the day and she'd book us to DFW the next day. We looked at the weather elsewhere for a few and flew to MRY for the day. Even better, I was able to get mileage credit for BOS-LAX-MRY-LAX-DFW.