I just read the AV Club's road-trip mix-tape suggestions (I was very excited to see Josh Modell's answer because I would run away with him if given the opportunity and Nathan Rabin's because he doesn't drive). While their responses are wonderful, especially the road/location specific ones, there is something missing from their list. For some time now, all of my road trips have begun with the same song: Kansas's "Carry on My Wayward Son." The melodic to electric build is well suited to pulling out of the driveway and getting on the road.
It's also the first song of a very specific road trip mix based entirely on songs from Supernatural, which sounds dorky and ridiculous, but consider this: it's almost entirely classic rock, which is the very basis of all good road trip mixes (that, and country, because it is so readily available on radio regardless of location). What's more, if you watch Supernatural (and you should), cross-country trips are a regular part of the show. If you had a cherry '67 Chevy Impala at your disposal, wouldn't they be a regular part of your life?
Why does "Carry on My Wayward Son" have to come first? Since the penultimate episode of first season, each season finale begins with a montage set to that very song. And I kid you not, the fine editing folk behind Supernatural give great montage. See for yourself after the jump.