I'm not "anti-leftovers" but I do think that disguising them is the way to go. When we eat leftovers, they are rarely in the same form as the original meal.
Here are some recipes I use when I have leftovers.
Mashed potato cakes
Fried rice and Frugal Leftover Fried Rice
Enchiladas. This is a great way to use up leftover pot roast or roast beef--pour some canned enchilada sauce into a casserole dish, mix some sauce with shredded cooked beef, chopped onions and cheese, roll up enchiladas, and top with more sauce and cheese. Cover and bake at 350 for 20 minutes.
Beef Burgundy Stroganoff
Chili (great way to use up cooked hamburgers!)
CHICKEN (or TURKEY)
Turkey or chicken paprikas
Cousin Sharon's Chicken & Biscuit Stew
Chicken & Dumplings
Chicken Fajita Soup
Grandpa's Dark Meat Chicken
Chicken Chili Blanco
Chicken & Noodle Casserole
Scarborough Fair Chicken Soup (I made stock with the turkey carcass, so this would be a great way to use it!)
Lo Mein (also works with pork, and--BONUS--uses up the leftover spaghetti!)
Pulled pork sandwiches (also works with chicken)