This is one of my favorite visual illusions. The goal is to count the number of times the players dressed in white pass the basketball to each other in the movie after the link.
It's a little tricky, because they are constantly moving around, but see if you can correctly count the number of times the basketball is passed - remember just between the players in white.
Don't spoil the illusion for others if you figure it out :)
SPOILER SPOILER SPOILER SPOILER SPOILER
The point of this visual illusion is explained in more detail here.
This illusion is an example of perception blindness. For example you might have counted the number of passes, but there was something else wrong with the video. If you didn't notice what was wrong with the video the first time, try to view it again. This time, watch for something odd.