Once my flight (of 1 hour flight time) was delayed over 6 hours. I heard from other passenger that if we file a complain, then we can get a full refund. In the end I was too lazy to deal with it, but I still think about it. There are other times I could have gotten compensation from airlines but I never took the time to do it.
I have a couple of Jewish friends who are very good with such things. They always get free stuff!