You can be as rediculus and unresonable as you want... or serious too, if you want!
The Soup Diet - Eat a bowl of soup (preferable vegetable or chicken noodle) before every meal to reduce your hunger, causing you to eat less then you otherwise would.
My husband had a relative that actually lost weight on the beer-and-cheddar cheese-diet. Blech!
I eat tons of salad, which my co-workers refer to as rabbit food. In their honor I propose the rabbit food diet, in which you eat only the pelleted alfalfa sold as food for pet bunnies, and all the carrots you can eat!
I actually went on my chocolate diet when I was 14. Here it is:
Breakfast: 3 tasty-cake cupcakes with chocolate icing
Lunch: Lettuce and tomato sandwich with chocolate milk and a large hershey bar.
Dinner: Hamburger, cottage cheese and desert of chocolate pudding
Snack: Chocolate ice cream with whip cream
This worked when I was 14, but I wouldn't do it now
You can eat all of your favorite foods, but you have to eat them all at the same time. Nacho cheese sauce on top of your ice cream! Refried beans and Jell-O! Hot dogs with chocolate frosting!
Make Your Own Fad Diet! (Game)
...if weight is an issue make it light beer 
