This is just awesome.  About a year ago, someone walked into a pizza place in Philadelphia called Rosa's, and asked if they could pay a dollar extra to buy a slice for a homeless person.  The rest of the story is a great example of 'paying it forward'.


Mason Wartman is the owner of Rosa's Pizza in Philadelphia .  He started putting Post-It notes on the wall each time someone donated a slice.  And in the past nine months, more than 8,400 people have paid it forward!


Last week, Mason was on "The Ellen DeGeneres Show" to talk about it.