If there's one thing that intrigues me, it's the pre-adult swim older audience late night programming. Now, all I know of are examples of what they put on before it was established. Even the criminally underrated, too hip for the room Saturday Morning Ed Grimley cartoon at some point. And then there was the analytical old cartoon package of "Toon Heads" which I actually got to see a couple of. And of course the not quite adult, not quite kiddy Space Ghost show meant for older audiences, but still managed to pop up on kid's merchandising. I think even the odd SGCTC albums were published under Kid Rhino, but I have to double check that.
And as we all know, SGCTC pretty much served as inspiration for the [as] block and the original tone of the odd shows within. I'm sure in the old old days of the network most of the late night line up was older cartoons from the 70's and 80's, but I can't confirm that. It's actually kind of strange because if you look at older CN material, you can pinpoint where it started to become a network based more off of modern shows, original programming, and the Doo hisself. I'm sure most of us know of the "Booboo Baba DeeDee" song (it was released on a CN soundtrack). It was an odd mix of current CN stars, Space Ghost characters, and a couple Looney Tunes characters singing about all the characters, new and old, on the network. In fact, that whole album was a mish mash of classic cartoon themes, current CN programming, a few more recent shows like Animaniacs and the only legally released instance of the Freakazoid theme, and a couple TV show packages.