Metallica - "Master of Puppets" & "One"
I 2nd these! They never got old for me, either. I don't even listen to metal anymore, but old Metallica always is worth a listen.
@Classic Song: Sonic 2 had more catchy songs in my opinion, but the bonus stages in Sonic 3 are definitely catchy in my ears~ xD I can't think of other memorable songs from S3 though..songs like the Marble Garden Zone and Carnival Night Zone left me with bad memories. >_<
Also, this is another favorite that stays catchy for me:
Sorry, I'm stuck on video game music right now. >_< Next song will not be from a video game, I promise! ^ ^;