I am enjoying listening to Podrunner Podcasts on one ear phone of my nano, turned up slightly loud and hanging aroundd my neck, no it is not in my ear, while riding for cadence. They have a whole series of techno music at various ranges of beats per minute. They also have some freeway to 5 k and 10 k which add in a warm up and then do a series of various types of intervals followed by a cool down. These work sequentially week by week on length and speed of intervals.
Note re the nano- I ride way out in the country on straight stretches with little or no traffic, but I still keep the nnan earphone out of my ear on the off road side so that I can hear traffic coming behind me.
I also enjoy the podrunner podcasts while doing cardio at the gym on the treadmill or precore.
marni