I don't Stumble that much, but I found this video recently doing so.
It's an amazing awareness test, as part of an ad campaign sponsored by the mayor of London. You can watch it without sound, but it's a little better with sound.
How many did you see? 12, 13, 14? You simply have to watch the video again after you've seen it once.
There's so many possible applications of this video. Of course, their message at the end is a great one, but you could apply it to other situations as well.
I met recently with my employees and we talked about some of the distractions that they face while working, such as computer games, texting, and IM. I hesitate fully banning any kind of diversion for days or times when it is slow, but when there are piles of things to do and people to help, I don't understand at all that they don't see all this stuff they should be doing. How do I make them be aware if they don't want to be?