We have a ton of greasy spoons/diners here in Central PA. Like any kind of restaurant, some are fantastic and others you'd never want to set foot in! There are a couple near us that have great--and very cheap--breakfasts (2 eggs, toast, potatoes and for $1.29, that kind of thing). A couple have fantastic home-made pies and soups, too.
A guy I used to work with was a huge diner fan. I'd like to say it was because he was a foodie but he really was just incredibly cheap and was looking for the cheapest food, no matter the quality. He even had a coffee table book of PA diners that he'd keep in the car so that when he was traveling, he could visit the diners and have the cooks sign the book! :roll: