Not too long ago, I was having a really bad day. I went to a Taco Bell for lunch, and the cashier said to me, "Well, I hope that you get to feeling better soon." with a smile on her face. She even handed me my lunch when it came out (compared to people normally picking up their orders themselves).
Little gestures like that from strangers actually cheer me up immensely. :)
But I also like hugs. <3