With your route set, fill in your stops. Why not stop in every state you pass through at least once to see a famous attraction or eat in a popular restaurant offering local cuisine? And don't overlook more obscure attractions that might be just as interesting but less crowded and costly. The Internet, guidebooks and smartphone apps are all good resources for finding things that pique your interest.
The Web site RoadsideAmerica.com (which also has an app) can help you find those quirky destinations -- for instance, if you're near Woodruff, Wis., check out the Forest of Chainsaw Totem Poles! Going to the Grand Canyon? Take a detour to Yucca, Ariz., to see the Golf Ball House.