I think most people take their ‘driving CDs’ selection pretty seriously. I know it’s important to me to have my favorite CDs in my car with me, ‘cause when I’m in my car it’s really the only time I can totally focus on the music… and I usually get tired of the radio programs real fast! And if I’m on a long trip, I MUST have my favorite CDs with me. Different moods call for different songs, of course… but what CDs are people keeping in their cars at all times?

I live in LA and with long commutes
need disc changer
I rotate every week or so

currently, I have:
Sting - Brand New Day (Import Single)
The Rippingtons - Sahara
Rap/Hip Hop - Compilation CD
Santana - Supernatural
Royal Crown Revue - Mugsy's Move

and I can't remember the other one...
I'll go check it out and get back to ya.

for long trips...it depends on my mood.
I have over 300 CDs. So, it takes a while to figure it all out.

found it:

the soundtrack to 10 Things I Hate About You

I went on a road trip through Colorado last year and one of the perfect moments of the trip was driving up over the San Juan Skyway when the sun was about to sink behind the horizon and listening to a CD by Stan DeWitt. It was an amazing view and his music set the right mood for the drive. That CD and the O Brother soundtrack are my favorite CDs to travel with. I would recommend them to anybody who is going on a scenic drive, or any sort of drive for that matter. Stan DeWitt: http://www.standewitt.com / O Brother: http://obrothersoundtrack.com/

It's kinda embarrasin'...but...we found, my family, that is...that ABBA was sort of universal! My aged Italian hubby likes it....I like it...and our 17 year old daughter likes it... and we did many 100km road trips for soccer and such...and it was usually a good choice!

Hey tree_hugger, sounds like you had a religious experience with the Stan DeWitt CD! Are you referring to his Long Days Journey CD? That’s the one I have. If so, then I can imagine how great it was for your road trip. It’s on my list too:
1. The Eagles
2. Stan DeWitt
3. David Wilcox
4. James Taylor
5. Wonder Boys soundtrack
6. Good Will Hunting soundtrack
7. Neil Young
8. Travis
9. Chris Isaak
10. Shawn Mullins

I had a Sting's Best of tape in my car before it was stolen and destroyed, plus a few others that were excellent for a real road trip.
And my son and I did a small trip in the van to the mountains. About five hours. When Julian was born he had a kind of a limp arm from his birth and I remember we kind of worked on it by pretending he was a Blues Brothers band member. We'd joke around and say, "I'm a soul man" put sunglasses on him. So I had that tape in the car.
Maybe he remembers it from his "therapy"!
We were worried he might have nerve damage (he doesn't!) so we just kind of played music with him.
I had some Scottish music in there too.
That was neat.
We played that Sting tape a million times.
Good thing, as when they found our car on a hilltop all burnt all my tapes were lost. Sure it's stupid but I miss them.
The Scottish ones were one of a kind.

I change with my moods. Right now, I am listening to Al Jarreau's Greatest Hits, Steve Winwood's "Junction Seven" and Oleta Adam's "Circle of One."