Krystals is good, haven't seen one outside of Georgia though.
If anyone has EVER eaten at In 'N' Out then they would say that is the best. I lived in Cali and never at anywhere else for fast food except the burrito stands.
In 'N' Out is , to my knowledge, only in Cali, Las Vegas, and I ate at one in Pheonix. Thier beef is never frozen, fries cut from whole potatoes every morning. They have secret menu items, you can get your burger "Animal Style". It is a 50's themed place and it isn't just decorated like it but the kids that work there are what you would expect from the 50's and the food is prpared the exact same way. It is probably the largest non-franchise fast food chain, owned by the same family for years.
My wife worked there when she was in high school I've heard everything about it and there seems to be a sense of pride with it's employees.