I've seen this other places, so I figured it'd be fun to create a list of the music that is played when Mets players come up to bat/in to pitch.
Here's what I know:
Daniel Murphy- What I've Done by Linkin Park , Shipping off to Boston by The Dropkick Murphys, This Town by O.A.R.
J.J. Putz- Thunderstruck by AC/DC
Francisco Rodriguez- Sandungueso by Tego Calderon
Carlos Beltran- El Esta Aqui by David Y Abraham
Johan Santana- Smooth by Carlos Santana
Mike Pelfrey- What I Like About You by The Romantics
John Maine- Seek and Destroy by Metallica
Oliver Perez- I'm Gonna Get You by Bizzare Inc. (according to an online source)
Ryan Church- Crazy Train by Ozzy Osbourne
Jose Reyes- El Mudo by Chacaron (According to an online source)
Wilson Valdez- Rock You Like A Hurricane by The Scorpions
Gary Sheffield- Swagger Like Us Remix by Kanye, Jay-Z et al
Bobby Parnell- 8 Second Ride by Jake Owen
Billy Wagner- Enter Sandman by Metallica
Cory Sullivan- Icky Thump by White Stripes
Nelson Figueroa- Lose Yourself by Eminem
Feel free to add more if you know any I didn't mention