Which anime or OVA do you think has the worst animation?

For me, probably the cheapest animation I've ever seen would have to be Sonic The Hedgehog: The Movie. This movie was released about the same time as Sonic Adventure (which I believe was in 1999), and yet it looks like it was made in the 70's.

Now mind you. You don't have to hate a film to say that it has bad animation. You can name a film that you enjoyed.

I don't care how bad the animation in Sonic The Hedgehog: The Movie was. It's still probably one of the best video game movies I've ever seen, along with Street Fighter II: The Animated Movie.