Here is a video in youtube (two parts) I found interesting to me and I would like to share it with you. Take some of your time and watch them. I would like to hear your comments on the topic they present!!
http://www.youtube.com/watch?v=eqjl-qRy71w
http://www.youtube.com/watch?v=1bUWcy8HwpM
http://www.youtube.com/watch?v=eqjl-qRy71w
http://www.youtube.com/watch?v=1bUWcy8HwpM