When doing online transactions, you probably see these boxes all the time that say “Please provide additional information”, or “Describe extra shipping instructions”, etc. How often do you write something in them?
I like leaving nice random messages for people when I know a human being will read them. Like the notes for the maitre'd on an opentable.com restaurant reservation. The one I left this week was “You Rock. You are a lovely human being. Gosh darn'it, people like you. Enjoy a great day!”
Next time you've got the chance, leave a nice note.