What kind of music do you like?
You can't go wrong with a little Professor Longhair.
Give us a genre. You can include the Beatles of course, since they transcend all genres.
70s rock and indie music mostly.
...you may not like all those, but they should be enough to remind you of other things you like.
You might also make a Pandora station, and see what turns up.
I don't think you can go wrong with pretty much anything from the 80's.
A little. Only in small doses. The closest I get to liturgical (Gregorian) Chant on a regular basis is Mozart's Requiem. Though that's less a chant and more a work of classical music art.
I dig some Gregorian chant. It relaxes me. Various Orthodox chants too.
If you're into rock, I recommend the Raconteurs.
Explosions in the Sky is great. Very good music when you just want to drive around and think about things.
Guns n' Roses