I just watched this one over lunch (yes, if there are only 24 hours in a day and you can’t change that, you can make a better use of your time): it’s a TED talk by Bryan Stevenson.
It quickly became one of my all-time favorites. I don’t want to tell you anything about it. Watch it. Simple as that.
Ah, by the way: it seems that TEDsters liked it as well. In fact, this talk received the strongest standing ovation ever seen at TED (according to Wikipedia).