Next time you pass a vending machine or gumball dispenser, check your change purse. If you have enough change to buy a soda or snack, tape the change to the side of the vending machine with a note saying "Snack's on me!"
If you don't have tape on hand, leave the change in the change dispenser at the bottom of the machine with a similar note. You will make someone's day!
How many times have you gone to the vending machine only to realize you don't have the right amount of change, or that you forgot your wallet all together? Help make someone's day and provide a free snack for them.
Encourage the recipient to pass on their good fortune and leave their change for the next person. See how long the chain lasts. Or commit to doing this act once a week at various vending machines. You could also do this with parking meters!
Next time you buy a soda or a snack, buy two. Leave one in the machine so the next person gets one free! It might not be the flavor they like, but they will either leave it for the next person or bring it to someone they know.
Attach a quote on kindness to the note you leave!