Do you need a reason to smile?
Some folks don't seem to ... they appear to have a smile ready to break out any time.
This worker at Del Monte's Warehouse No. 8 was unloading pineapples from a truck and into a very cold storage room. Every time his forklift zoomed past, his smile seemed to get a little wider.
It made me smile. I liken it to the contagion of yawning, but a lot more fun.
Smile for any reason or for no reason at all, it makes everything better.