When I was younger, Cartoon Network had a show called "O, CANADA" that was mainly dedicated to running animated shorts from the National Film Board. It was only on once or twice a week at some hour way past my bedtime, so I'd sneak upstairs to watch it with the volume down whenever I could get the chance. I remember the half hour it was on always felt much too short.
Anyway, the NFB recently put more than 70 animated shorts streaming online - the player can be slow but there is a lot of really high quality, cutting edge animation dating back more than half a century.
This short was my favorite on O CANADA and I always wanted to watch it again. That film, and many others, are here.
Update: Since the player is a little off - try Youtube.