I don't know if I will try any of these but they are something to consider.
1. Lemonade Diet. Drink lemonade 6 times a day, and no solid food for a week.
2. Beverly Hills Diet. Eat fruit for breakfast, carbs for lunch, and protein for dinner.
3. The 3 Hour Diet. Eat every 3 hours. For each meal, eat protein the size of a deck of cards, carbs the size of a Rubik's cube, and enough fat to fill a water bottle lid.
4. The Cabbage Soup Diet. Eat only 2 bowls of cabbage soup a day, with additional vegetables, for one week.
5. The Fast Food Diet. Eat healthy for two meals a day, and fast food for one meal (skipping the french fries and soda), and walk a mile per day.
6. The Nutrisystem Diet. Buy a 28-day supply of food from their website for $300, and only eat their food.
7. The Rachel Ray Diet. Prepare meals using Rachel Ray's recipes. Don't eat anything else except for vegetables.
8. The Shangri La Diet. Eat only bland foods, and one teaspoon of sugar water for a morning snack, and one teaspoon of olive oil for an afternoon snack.
9. The Sugar Busters Diet. Eliminate all sugar from your diet including bread, beer, soda, rice, potatoes, carrots and bananas.
10. The Morning Banana Diet. Eat 1 or 2 bananas for breakfast with a glass of water, and then anything else you want for the rest of the day, except dessert, but don't eat after 8:00pm.
11. The Raw Food Diet. Eat only raw fruits and vegetables. Don't eat anything cooked. You can have avocados, nuts, and bananas.
12. The Negative Calorie Diet. Eat only foods that supposedly have negative calories, such as celery, cucumbers, lettuce and green beans.
13. The Grape Diet. Like it sounds, eat only grapes and drink only water.
14. The Mono Diet. Eat only 1 food at each meal, like 1 potato, or one piece of fish. Similar to the Beverly Hills Diet.
15. The Ice Cream Diet. Eat only salads, fruits, and vegetable soup, along with a small bowl of ice cream each night.
16. The Grapefruit Diet. Eat only one-half a grapefruit for breakfast lunch and dinner, along with a small salad.
17. The Caveman Diet. Eat only vegetables (except potatoes), eggs, fruit, nuts, berries, and fish or chicken.
18. The Three Day Diet. Strictly follow a menu for three days. Similar to the Ice Cream Diet.
19. The Metabolism Diet. This is a restricted calorie, low carb diet that you follow for 7 days.
20. The Special K Diet. Eat only Special K with skim milk and fruit for breakfast and lunch and then eat a sensible dinner.
Source: http://www.dietdigest.net/best-fad-diets; http://www.free-fad-diets.com/top-ten-fad-diets.html