If we're talking right now...jeez I have too many.
If we're talking the songs I loved as a kid and continue to love now, well that list is more manageable:
The Pixies - Where is my mind?
Misfits - One Last Caress
Joy Division - Transmission
Notorious BIG - Hypnotize
These always remind me of my youth and when I was discovering music through my extended family. I'll never tire of these songs.