Whatever catches my ear. Never been a big metal fan, or hiphop, though there are occaional exceptions to that. I've found myself oddly enjoying Black Eyed Peas, particularly the Pump It single, which is cleverly done.
I don't necessarily favor particular artists, though I still have a soft spot for the B-52s, the Go-Go's, Bowie, Springstein, The Eagles, Bob Seger, Buddy Holly, U2, Danny Elfman, John Williams, Weird Al, Glenn Miller, B.B. King and Ray Charles. Nothing very edgy there.
In general I like a fat horn section, so things like some of the bigger budgeted Chicago blues groups and the Big Bands of the 30s and 40s are often what I listen to on long road trips. I enjoyed some of the late 90s groups reinterpretation of the sound. Folks like Royal Crown Revue, Cherry Poppin' Daddies and Squirrel Nut Zippers.
I also like a good story, which again doesn't always have a given artist. Something like the Dixie Chicks' "Goodbye Earl," or Julie Brown's "The Homecoming Queen's Got A Gun." Though in our post-Columbine world would probably never see the light of day.
Which leads to my other genre I love. Paradoy and comedy songs. I drive my mother-in-law nuts because she is always wanting to play syrupy Christams fare, and I sneak in some like Green Chri$tma$, or Christmas at Ground Zero, which has to be the cheeriest nuclear war song ever.