Even though I'm an atheist, I just want to say "Happy Mardi Gras!" With that out of the way...

Old cartoons you never heard of...
Little Audrey/Noveltoons:

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This was made decades before Rainbow Brite and Lucky Star, this one in particular was made in 1950. I noticed that the art style looks similar to current Japanese anime.

Betty Boop:

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This episode in particular was banned for the use of laughing gas. Betty Boop back then was synonymous with controversy back in the '30s and '40s, much like how Seth McFarlane and Drawn Together are today. Plus, this also featured Ko Ko the Clown and Max Fleischer as the guy with the pen.

Heckle and Jeckle:

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Of all the stuff that came from Terrytoons, these Talking Magpies happen to be my favorites. Plus, Ralph Bakshi used to work at that aforementioned company.

That's all for the old cartoons that you never heard of, but I might have to find a few more that are worth mentioning. As for that man who got busted for having only hentai that I found out about from Sirkowski; I have to say that I agree with Sirkowski on that hentai ordeal.