The increased media attention on high-profile food competitions has encouraged many restaurants to start their own in-house challenges. Coupon Sherpa was so fascinated by this phenomenon we compiled a list of 40 restaurants offering free food to diners who manage to scarf down -- and keep down -- massive quantities of the house special. Restaurants offer free food, cash awards and/or T-shirts to those who complete the challenge within a specified time limit.

A few examples include:

Denny’s Beer Barrel Pub
Location: Clearfield, Pennsylvania
Food Challenge: If you have two people and three hours, take on the Beer Barrel Belly Buster. The 15-pound burger includes a 20-inch patty, 17-inch bun, two onions, a head of lettuce, 25 slices of cheese, three tomatoes, mayo, mustard, relish and ketchup. Finish the challenge in three hours and it's completely free! Fail and it'll cost you $49.95.

Jack 'n Grill
Location: Denver, Colorado
Food Challenge: As seen on the Travel Channel's popular "Man vs Food" show, the famous Jack-n-Grill seven-pound burrito eats more like a casserole than a burrito. Women who complete the challenge receive free food for life at Jack 'n Grill. Only three women have ever finished the challenge and word on the street is they never returned for more.

Fat Sandwich Company
Location: Champaign, Illinois
Food Challenge: Eat a Big, Fat and Ugly in under 15 minutes and it's free. The challenge includes two rolls, four cheeseburgers, double cheesesteak, chicken cheesesteak, gyro meat, grilled chicken, bacon sausage, mozzarella sticks, chicken fingers, chicken nuggets, mac-n-cheese bites, fried mushrooms, jalapeno poppers, pizza bites, onion rings, hash browns, mini corn dogs, American cheese, mayo ketchup poppers and pizza bites.