In our 7.5 years of marriage I have found quite a few recipes that work great for this. With chicken I make several different chicken casseroles, chicken enchiladas, chicken and dumplings or chicken soup. With Ham I make Ham cheddar & broccoli sandwich ring, cheesy ham and potato casserole, ham and cheese omelets, ham and potato soup, or pinto beans (which I don't make often since my husband doesn't care for those). With beef or venison I make beef stew or soup and depending on how much is leftover I might make pulled bbq. Hamburgers or meatloaf work great to grind up and use in pasta dishes or Stromboli.
I do like to make one dish dinners. However when I make them I try to make just enough for our family without leaving much leftover. Since my husband doesn't like the leftovers I know he won't help in eating them and I do not enjoy eating the same leftover meal for lunch every day for an entire week. I have done that on occassion to avoid throwing something out, but I really don't prefer it.
Tonight for dinner we are having a delicious
P.S. I'd love to hear how you use up your leftovers. Feel free to leave a comment with a recipe or a link.