I like to cook. So, one small home improvement that has improved my life a lot has been venting the over-the-range microwave fan through the exterior wall. The tools and parts were pretty cheap. (I already had a stud finder, and the microwave exhaust duct was not expensive, but links for both are below.) Plus, this project was fairly simple, and and it has really cut down on the smoke and odor in the kitchen and in the whole house.