This video name simply Doctor Who 50th Anniversary Project is a simple animation going from the First Doctor all the way through to the Eleventh Doctor (and yes the War Doctor is there too.)
That description doesn't really tell you what's so great about it. Not only does Chang Dai capture the character of each of the Doctors in the animation, but the transitions from to the next are so nicely done. And then the final moment when the Doctor is surrounded by so many of his friends is very touching.
Well worth a few moments of your time if you enjoy Doctor Who.