Maybe you'll see a good deal on Ramen noodles.

2 packages beef flavor Top Ramen
Salt
3 cups water
1/2 pound ground beef
1/2 cup mushrooms, sliced
1 jar (15 1/2 oz) spaghetti sauce
3 tablespoons Parmesan cheese
1/2 cup onion, chopped
1/2 cup milk
1 egg
8 oz mozzarella cheese, shredded
1 pizza pan
Aluminum foil
Cooking spray

Cover pizza pan with foil, building up edges to form a 1/2 inch rim. Lightly grease with cooking spray. Cook both packages of noodles in water with a pinch of salt. Set aside the flavor packets. Drain the noodles and set aside. Brown the beef, onions, and mushrooms together. Drain excess fat. Stir both flavor packets into the meat mixture and set aside. Beat together: egg, milk, and Parmesan cheese. Stir this into the cooked noodles. Evenly spread the noodle mixture over the foil on the pizza pan. Pour spaghetti sauce over the noodles and sprinkle the meat mixture over it. Top with mozzarella cheese. Bake 20 minutes at 350 degrees or until pizza is bubbly and brown. Let stand 5 minutes before slicing.

I haven't tried this, and kind of have my doubts about the noodles because there sometimes they can get soggy so fast. But what the heck, if I see a sale, I'll give it a try and let you know.