In the summer, when it's small, reggae. When it's big, or in the winter, (I know I'm showing my age here) Jane's Addiction's Coming Down the Mountain, and a lot of Smashing Pumpkins gets me amped, but any heavy, fast music will do.
When I'm shaping, reggae or jazz. When I'm glassing, Hendrix makes the resin swirls sweeet.
For 20 plus years, this song has remained my favorite all-time pre-surf psyche up anthem. It's called "Try It" by the 80's90's Boston metal-punk geniuses The Bags. When I'm debating in my head whether to attempt a dicey drop, it makes me go for it.
I try and listen to something that will get me amped up just before I paddle out, but half the time I will get some random weird song stuck in my head, and like someone else posted, I'll end up singing or humming the damn thing to myself the whole session.
Sometimes if it's a particularly bad song, and I'm amongst friends, I'll sing it real loud so I can get it stuck in their heads also.