My parents just had this happen to them. The buyer simply didn't show up to the closing (and couldn't be reached by phone). They found out a few days later that supposedly her husband served her with divorce papers right before the closing.
We sort-of had this from the opposite end when we purchased our current home. We were supposed to close on a Friday (I even came in from out of state) but due to a mortgage company issue we were not able to. The sellers were mad that they therefore could not close on the house they were purchasing that day, so they cancelled our contract. We were able to close on Tuesday, but it wound up costing us more because they refused to pay for any of the repairs they originally agreed to.
We sort-of had this from the opposite end when we purchased our current home. We were supposed to close on a Friday (I even came in from out of state) but due to a mortgage company issue we were not able to. The sellers were mad that they therefore could not close on the house they were purchasing that day, so they cancelled our contract. We were able to close on Tuesday, but it wound up costing us more because they refused to pay for any of the repairs they originally agreed to.