I've heard Dr Kataria talk about laughing with a cell phone by yourself for stress relief. Last night I was waiting in the St Louis Airport late in the evening to pick up my daughter. I called my husband to talk for a few minutes because I was getting bored. A little later, my cell phone rang and it was my husband, saying "laughter phone call! We laughed together for a good while with some very hearty laughter. I felt much better and refreshed.
I looked around me during the laughter call to see what people's reactions were. You know what? People were so involved in their own tasks and their own world that no one even noticed or cared. But I had a good time and felt much better!