It kinda depends on what they're motivating me to do, but in general:

A New Level - Pantera
Head Up - Deftones
Kings of the Kilburn High - Flogging Molly
Strawberry - Everclear (pretty fucking weak, I know. I don't really like the song that much, but a few of the lyrics and the general theme hit home).


I'll add more if I think of them, I could make a longer list of songs that motivated me to do certain things...