@alag I honestly leave my iPod on shuffle and see what pops up. Thrash, Death Metal, Deathcore, Metalcore, Hardcore, Nu metal, Tech Death. There’s some Eminem, Chemical Brothers and The Prodigy thrown in there too. Then at the slightly more mellow end everything from Green Day, The Used, Offspring all the way to Alanis Morissette.
I can mostly use almost all music for some for of motivation, but when you hit a wall something with a deep, groovy beat helps for me.