How exactly do they name the most calming songs? "Mad World," while one of my favorite songs at the moment, simply doesn't feel like a driving song. "Come Away With Me" does a bit (sort of has that flowing feeling). I don't know.
I will say, though, that any song with a realistic siren in it is pretty unsafe, because it gets me frantically searching behind me for the cops
One other one that used to freak me out all the time is "How Do You" by Radiohead. I guess it was due to my speaker placement in the Eclipse I used to drive, but the thud at the very end of the song sounded either like something had banged the bottom of my car, or my trunk release had gone off