There is not a whole lot more satisfying than seeing justice dealt. I say justice because should be more appealing than revenge because justice is what someone deserves but revenge can be bitter and spiteful. Karma is the universe's built in judge and jury. When you do ill to someone else it has a way of coming back to you. It may not even be in this lifetime (suspense is killer!) but it will come back to bite you in the butt. Take the case of the 3 year old birthday dinner I just took my little princess on. She love Applebee's. I don't know why, but she does. She orders macaroni and cheese and even on the menu it states that it is the same exact Kraft macaroni and cheese I get at the store for $0.88 but they feel ok charging $4 for it. Whatever, it's her birthday, get whatever you want kiddo! Where I have the issue is the service we received. Part of what is built into the price of the food is the atmosphere, cost of food, and wages of the staff. So as a person who has been on both sides of the restaurant experience (server, cook, dishwasher, done it all) I understand how it works, so when Jimbob (name's changed to protect the accused) came up to our table and asked "What do you want?" I was tempted to say "a new waiter." He didn't care or say anything when we said we were celebrating my daughter's 3rd birthday, didn't bring out a dessert, or even mark off anything on the check. In short he didn't even acknowledge my child on her special dinner. Turns out that being a server is one of those opportunities for karma to be applied instantly. If you do awesome and make the customer feel good, tips are generally good. If you suck at life and make people feel like they didn't have a good time, tips will go down the drain. There are exceptions to the rule, but you get the general idea.
I think you can guess how awesome our waiter did when he picked up the check :)