As much as possible, we try not to to have leftovers since we love food freshly cooked. If ever we have one, we just reheat or recook them so we can still enjoy eating them. But there are certain foods that we usually leave overnight since they are better when left overnight, just like foods with soy sauce or those that needs to be marinade.
Most of my leftovers usually ends up as part of 3 different recipes: Pizza, Frittata and Fried rice. If you cut leftovers in small pieces you can use them as toppings for the 3 dishes I mentioned.I recently made fried rice with the leftover Christmas ham while I made Pizza out of the leftover turkey. Sometimes I just heat the frozen leftovers in a slowcooker and eat it the way it is.