A few weeks ago I delivered several stuffed 'happy' flowers to several women at work (Toys R Us). I also attached Smile cards to each and every one. I know some people have taken it to heart, as I've heard about 2 other kind acts snowballing off that one.
Of course, I got accused of doing it, but I denied it completely. I wanted them to always wonder who it was, and hopefully they'll pay it forward.
