When I was in college, I regularly invited friends for dinner, sometimes up to 8 people. I almost always made some spaghetti with tomato sauce, nothing fancy, but lots.

With 3 friends, I started making this a habit: Cooking for more people= less cost for each one. We took turns, each one was hosting once a week. One of my friends had significantly richer parents than the rest of us, so he always made the fanciest stuff. He didnt mind, we enjoyed it. Someone would bring beer or wine, someone sometimes an additional salad or dessert. It was great, only cooking once but having four different meals each week.

Also important was the aspect of saving time. Since I worked after school, usually until 9 pm twice a week, I only showed up for the food at my friends place. The ones that had time would show up earlier, help cooking and already warm up the party.

I know most of you dont think it saves that much in money.. its certainly not free, but the social aspect of it was great, it saved me a lot of time and cooking for friends once a week is definitely more fun than preparing dinner for one each evening.