Music that has a beat that matches your foot strikes can really help get you moving and keep you going while you're walking.
I listen to music a lot while I use my treadmill. I love it.
I even use it to reward myself for meeting goals. When I want to purchase new tunes, I have to earn them.

Works for me. It keeps things fresh and I'm looking forward to the additions. It gives me a reason to go a little farther.