Don't know how many people know this, but the episode of Pokemon, "Electric Soldier Porygon", is one of the most famed banned episodes known. Many times, certain episodes of Pokemon are banned for reasons dealing with censorship, such as an abscure sexual reference, but in this episode is quite different. In the episode, a strange new Pokemon is discovered, Porygon, as is a way to enter the "computer world". Of course, Ash and company are soon drawn into the world, as are Team Rocket.
Seems innocent enough, right? Well the animators seemed to have made a quite error while animated the episode. In one scene Team Rocket fires missles at Ash and friends, only to have Pikuchu destory said missles a Thunderbolt. The result was a flashing red and blue explosion that put 800 Japanese children in the hospital for epiletic seizures. After this, the show was put on hold for 4 months and nearly banned completely, but in the end, the single episodes was simply banned for good, from everywhere in the world.
Just thought I'd post it because it really interested me. I know I've heard jokes that "anime causes seizures" but I never stopped to think that maybe it was true. If you wanna read it from the source, check it out:
http://www.serebii.net/anime/banned.shtml