Every time I see the question of "What song is stuck in your head?", immediately I start thinking of a song, even if I wasn't just before. Right now my head's shuffling between the songs on the Zelda 25th anniversary cd. I love that cd. If only I could go to a Symphony of the Goddesses concert.
I almost always have a song stuck in my head. Right now it's the theme for Targitzan, Despotic Dizzy Totem God from Banjo-Tooie (the composer is Grant Kirkhope). I like most of his music, and the boss songs are really memorable.