“Invader Zim” was a cartoon series that was produced for Nickelodeon in 2001 but only ran two seasons before being cancelled. Evidentally, it had a big fan base because now it is a cult hit. You can occasionally see an episode on NickToons from time to time.
DVD’s, merchandise, and apparel related to this cartoon have a great sell-through rate on Ebay.
For more information, here is the entry on Wikipedia.
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