Walking around with music playing from your backpack is neither a way to make friends nor influence people; it would likely act as a turn off in many social interactions.  There is a type of person that goes for technology like this and that is why I am halfway certain that the Reppo II Backpack will sell like hotcakes.  Would I buy one of these?  Absolutely not, don’t be absurd.  I drive a car and my medium of choice is still the compact disk.  The people that would buy a Reppo II backpack are those that really want other people to like them for their music and those that like to go outside and dance.  I am neither so I will not bother.