Gratitude Note - An activity for closing a Positive Psychology Workshop

After a long workshop on Positive Psychology or any of the elements within the ambit of Positive Emotions, Engagement etc, it is always nice to end the workshop on a "feel good" note. One interesting activity that can be done would be to ask the participants to use Post-It notes and write a message of gratitude for any of the fellow participants. It can be written for one or many participants. After writing, the writer can just walk across the aisle and stick the Post-It on the back of the dress the receiver of that note is wearing. To make it more interesting, the Individual who writes the most notes, gets a chocolate (If you are a facilitator, can you arrange for a special prize?)