I think one of my favorite things to do is leaving gospel tracts and/or Gospel of John’s and random locations. Usually this is called the act of serendipity. I remember this word back in the day when I used to do the currency tracking of Where’s George./
I know some people leave Easter tracts with Easter Candy; Christmas tracts with the Christmas items in the store. Or you can do like the one I did above, I was at Chick-fil-A, and they had these flowers there. They had the fork for a card, so I put the water tract in that spot. It makes it more interesting if you leaved a special themed tract in a special themed area.
serendipity – finding valuable or pleasant things that are not looked for
 Using Gospel Tracts As A Witnessing Tool