You can Print Free Thank You Notes.  There are 4 per Page.

You can print free Thank You Notes and keep them with you
for the times you see someone
Involved in a Simple Act of Kindness.

You can also give them to someone who made you laugh or smile,
or to someone who provided exceptional service.

When you see someone who has done something kind, you might want to
hand them a Thank You Note and say
"That was really nice of you, I want you to have this."