In an advanced workshop class I took in my undergraduate work, there was one day my instructor would not be in town for class. Instead of canceling class, she decided to have a collegue of hers come in and present a writing to music activity. The experience was awesome and the activity is one I have grown to love more and more.
Yes, we were all veterans of this certain writing program, but I feel anyone who loves music could find ideas coming to mind with the driving rythm of a favorite song or group, or some new music might generate ideas.
A word of caution here. If you really get into music, like I do air-drumming more frantically than Animal from the Muppets, then I suggest borrowing a CD from a parent, friend, the library, basically anyone who will trust you with his/her CD. Writing to familiar music can be distracting if you are singing, strumming, or drumming while trying to generate ideas. If I borrow a mellow CD I am not familiar with, I find it easier to listen to the beat and let my mind generate whatever ideas it might.