I love this mine came in an email with a poem attached to the picture -

Smile for you
Smiling is infectious, you catch it like the flu
When someone smiled at me today, I started smiling too.
I passed around the corner and someone saw my grin
When he smiled I realized I'd passed it on to him.
I thought about that smile then I realized its worth,
A single smile, just like mine could travel around the earth,
So, if you feel a smile begin, don't leave it undetected
Lets start an epidemic quick, and get the world infected.

Keep the smile going by sending this on to a friend,
Everyone needs a smile!!