One thing you can almost always get is really good hotel rates. Just ask an agent for the distressed traveler number. They will usually have a pad of small sheets giving a number to call, which is a sort of travel agency that contracts with hotels near the airport for very good rates. This doesn't imply that the airline will pay for the hotel, but it does get you pretty good rates. Occasionally even this won't work, like when a blizzard comes through a hub and they just are out of rooms. But you can use that service even if it has nothing to do with the airline. (You might not be able to use it early in the day, or for a multi-day stay, it's mostly for one-night rooms that are still unsold late in the evening.)