Music while you Ride?

but that may be to do with me wearing glasses.

I definitely have to look around for longer when I'm wearing my glasses. My frames obscure important points so I always triple check compared to double checking when I'm not wearing them.

The worst is when I'm head down up a hill and when I glance up my glasses get in the way, I have to look over them which is fucking annoying.

The accelerometer song selector for the iPod touch is pretty cool,
chooses a song depending on how fast your moving.

Name of said app please? I need that in my life.