I came across an anime called Paprika shortly after it came out on video. Knowing almost nothing of the movie beyond the bizarre box cover, I decided to buy it. It's now one of my favorite anime movies with one of my favorite giantess scenes.
The movie was directed by Satoshi Kon, the Japanese auteur behind surreal anime classics like Perfect Blue and Paranoia Agent as well as the critical acclaimed Tokyo Godfathers. Though Paprika doesn't quite live up to some of his other films, it's still a very enjoyable trip down the rabbit hole into the world of dreams.
The movie centers around an experimental device that allows therapists to see and even enter their patient's dreams. The device is stolen, giving the thief control over the dreams and minds of others. Chaos and madness ensue and it's up to psychiatrist Atsuko Chiba and her daring dream alter ego Paprika to set things right.
Paprika is a fantastic film full of mindbending scenes that blur the line between dream and reality.The climax has Dr. Chiba grow gigantic in the middle of Tokyo to face off against the Big Bad.
The video below shows the giantess scene. Since it takes place right at the end, there are spoilers for those who haven't seen the film yet.
I had to cut a bit of the scene because of Youtube's policies. If you want to see the unedited version, you can find it here.