Via the Daily Beast
Keep in mind that the story is anecdotal, and the images in the video are from the video creator not Nancy Cartwright. Even so, Bart makes the perfect Scientologist.
Update: Since posting Fox had the video removed due to copyright reasons. I'm guessing some substance hit a fan somewhere.
The gist of it was Nancy Cartwright allegedly robo-phoning people leaving a message using Bart Simpson's voice and persona. It was an invitation to her speaking at a Scientology event.
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