Act of Kindness

The other day I was driving north on the New Jersey parkway.  Because I did not have exact change,  I had to go through the cash booth.  The line was long and slow.  When I finally got to the window, the toll collector motioned for me to go through.  Not understanding, I handed her a five dollar bill.  She said, "the card before you paid your toll".  I was wowed...this has never happened to me before!!  I decided to pass along the act of kindness, I paid for the next two cars. 

Later I wondered how often does this happen?  I guess it doesn't really matter, as long as I pay it forward...