Madonna - Hung up
Britney - Gimme more
Lady Gaga - Dance in The Dark
Christina Aguilera - Elastic Love
Depeche Mode - John The revelator
Dragonette - True Believer
I think I don't have 1 favorite song but there are some that never get old for me (Since U Been Gone is the first one I can think of) and some that always makes me happy (Crazy Little Thing Called Love, Wouldn't It Be Nice, Any Way You Want It, Red Light Spells Danger, They Don't Make Them Like They Used To Do, Rocky Horror Picture soundtrack, some The Darkness songs).
I don't have one. I'll name a few faves from my faves.
Michael Jackson - Wanna Be Startin' Something
Madonna - Ray of Light
Janet Jackson - Funky Big Band
Mariah Carey - Until the End of Time
Beyonce - Schoolin' Life
Stevie Wonder - As
Marvin Gaye - If I Should Die Tonight
Aretha Franklin - Ain't No Way
Linkin Park - Waiting for the End
Kings of Leon - Knocked Up
The Killers - When You Were Young
Death Cab For Cutie - Summer Skin
