It really depends on my mood, but it's usually some kind of Heavy Metal.
- Thrash Metal (Old Metallica, Slayer, Megadeth, Testament,....)
- Heavy Metal (Black Sabbath, Dio, Motorhead, Iron Maiden, Judas Priest, Venom, Pantera, King Diamond,....)
- Doom/Stoner Metal (Down, Type O Negative, Paradise Lost,...)
- Death Metal (Death, Morbid Angel, Cannibal Corpse, Obituary, Vader, Krisiun,...)
- Blues (Jeff Beck, Robin Trower, BB King, Buddy Guy, SVR, John Lee Hooker, Muddy Waters,....)
- Jazz (Louis Armstrong, Ella Fitzgerald, Gershwin's compositions,...)
- Rockabilly/Psychobilly (Stray Cats, Nekromantix, Reverend Horton Heat,....)
- Old Punk (Black Flag, Discharge, Ramones, Social Distortion,....)
I've got over 1000 CDs; it's a little hard to list all the genres and artists.