This has been discussed in other forums, but I thought it might be interesting to ask the question here among our, ahem, age group...
What kind of music, if any, do you like to listen to while riding?
Personally, I never use headphones when riding on the road. It's both an aesthetic issue and a safety one for me. I like to hear the sounds of nature and of my bike on the road. I also like to hear the sounds of any large metal objects that might happen to be bearing down on me.
On a trainer, though, it's another matter. Riding to music is, for me, an essential part of the trainer experience. In fact, it's part of the workout for me. I like to spin at something between 80 and 90 RPM, so I try to use songs that have tempos of 160-180 beats per minute... pretty up-tempo stuff! It really helps me to keep my pedal cadence where I want it.
My current trainer workout playlist is mostly a mix of U2, Bruce Springsteen, Rolling Stones, and Midnight Oil.
Does anybody else like to ride to music, either indoors or out? And if so, what works for you?