I remember when I used to go to a fitness club, music did help the routine go by faster. Not that it made me move any faster, but it takes your mind off things.

Many US states have rules against using headphones while operating any vehicles on-road. You can usually have ONE earphone (especially if it's for an intercom or communications gear) but not two.

I don't like the idea of even one earphone however, I would think it would impair your ability to localize sounds, and I consider that pretty important at least when riding on-road.
Sooner or later I plan to get one of these:
http://www.tigerdirect.com/applicati...5772&CatId=193
and just get a cheapo 1 or 2-gb flash player to stick inside it, nd hang it from the handlebars. I have seen that there are lots of external speakers you can buy, but they are larger than ideal for mounting on a bicycle--and with this bag-speakers thing, if you happen to drop the whole thing, the $10 bag-speaker actually helps protect the much-more-expensive MP3 player inside.
[edit]
...Okay, "sooner" is now.
I ordered one of them bag-speaker things and a MP3 player as well, cause I didn't have one either:
http://www.tigerdirect.com/applicati...473&CatId=2761
If either of these things is total junk I'm sure I'll be complaining about it here.
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