Answer:
Of these things - I have two. One for me - and one for you. And when you ask about the price, I simply smile and nod twice.
It is weightless, you can see it. If you put it in a barrel it will make it lighter?
What is that you will break everytime you name it?
What can bring back the dead. Make us cry, make us laugh, make us young. Born in an instant yet lasts a life time?
What can be seen but never found that only hides in the unwound?
People take me on walks and I run and have fun. What am I?