LittleBear LOVES music. If we're listening to music in the car, he's often either singing along (in his own way) or, more recently, tapping along with the beat, either kicking his legs or banging toys together.
He also loves to dance when we are singing to him (which we do a lot). He picked up a "bob your head side to side" move from his Mommy, and he's also started dancing with his legs sometimes.
Here's a fun video we got just the other day of him dancing to the music. (Yes, he was dancing to the music you hear, and yes, I do have some songs from the Night at the Roxbury soundtrack on my iPod.)
As a bonus, here's a video from about six months ago of him in his doorway jumper. This time, the music you hear is dubbed in -- he was just jumping around randomly -- but it's still fun to watch!