I like to take a recipe and fix it in several different ways. For example, I'll make shortbread two or three different Christmas shapes, then use some of the same dough but add lots of walnuts and roll in powdered sugar after baking (these are called "russian tea cakes) and for another batch I'll make ovals that I will dip in melted chocolate when they are cool.
Another time I've made variants of my hermits dough-- one the regular hermit another the chocolate chip version and the last one a fruitcake version. (Adjust the spices and so forth, of course, but the dough stays the same.)
Lastly, with sugar cookies, I will sometimes sprinkle crushed up peppermint on some, cinnamon sugar on others, and colored sugar on the others.
For what it's worth, no matter what I make, the chocolate chip cookies always go fastest.