I went shopping today, to buy a feather for my hair, some nappies for the babies, and bits like that. I chose a worthy feather, walked up to the counter and chatted with the lady as she served me. It was during this conversation I of course told her I was a singer (la, di, da) and in my silly flamboyant way, managed to really make her laugh heartily out loud. As I walked away I looked back on my short performance and was glad I had made her smile.
I think that remembering to rejoice in life is the most important key to emotional, and probably most physical health. So much worldly conversation is focussed on the negative, but I try to remember that this world was created by, and belongs to God. And the good guys win in the end you know!
I also think that no smile, or laughter that you give to others in your day goes unnoticed, it can always bless someone, and your happy heart will always bless you.