Oh so right on the ipod, etc. My sister was with me and she was running (my knees don't run) and she was all wired in. I tend to like to hear what is going on around me so don't wear one.

There probably isn't an answer, I know even a bell gets old and you get sore thumbs if in a highly congested area.

I certainly learned a lesson as a walker though to never assume no one is behind you when making a move to the right or the left!