Tunes while riding

I am curious as to how many people listen to their iPods/MP3 players while riding.

I love listening to music. IMHO, the iPod is one of the best inventions ever! I love using it to play music to match my moods, help me get thru workouts, start my day, lift my spirits on a crappy day, and ending my day as I drift off to sleep to mix of classical, new age and piano.

What are some favorite tunes you listen to while riding?