Random Acts of Kindness

I was on my way to Lincoln (JDA Agility Show) on Friday when I passed a car with a bumper sticker that read 'Commit Random Acts of Kindness' and this got me to thinking.
Recently I have received several unexpected RAoKs - not major things, just unexpected, like the lady who paid half my carparking fee at the hospital when she saw I hadn't got enough change. As a beneficiary it changed my outlook on the day, making me so much more good-humoured and 'one with the world'. RAoKs also have a feel-good factor for the benefactor, who knows that they have done something appreciated by others.
So, I got to thinking more: what if we all decided to do at least one Random Act of Kindness a day? It would have to be spontaneous, not pre-planned, and need not be anything major. What happens is that you become far more aware of the needs of others, and are actively seeking opportunities to commit the RAoK. Recipients benefit, and so do we. The world would gradually become a better place to live as we all looked for opportunities to help others in some way - just once a day, and still with a choice of whether to act or not.
What about it? I'd love to hear comments about whether you thought it was worth a shot.
Edited to add: always check first that the RAoK will be acceptable - not all blind/elderly people want to cross the road.........