All. The. Time. Music can be an extremely effective creativity booster (especially for cardistry), and is also a great tool for getting focused while practicing. I've found that different genres can definitely produce different results, so experimenting with different genres can really help you find something that works with your style of practice. I prefer more relaxing music while I practice because it makes me do things smoother. Genres like singer/songwriter are good for this, and it helps to have a female vocal. Artists like Norah Jones, Tristan Prettyman, Leighton Meester, and Lights' album Midnight Machines would fall into this category and are artists I like listening to.