Every runner I know, with the exception of my Dad, listens to some tunes while running. I have found this can have a HUGE impact on your run. Music is awesome because there are songs for your every mood: Angry/Frustrated: Evanessence and Green Day, Happy/Upbeat: Black Eyed Peas and just about everything on Kiss Fm and B96, Mellow: Country works well for this, and Michael Buble fits into all categories! :) He's a personal favorite! But whatever your mood is, it is important to recognize the mood you are in and choose music accordingly to have the best workout possible! Otherwise you will become bored during your run and not have a very good run.
Another music trick is your Power Song. The Power Song, is the one song that for one reason or another really gets you going. It has been proven that if you use a poser song, you run faster during the duration of that song. It is recommended that you use the song when you are having a hard time pushing yourself farther during your run.
My Power Song: Nysnc: Here We Go.. No idea why but it always works!
Try it! What's your power song?