Looney Tunes, Tiny Toons, Spongebob, The Mighty B!, Catdog, Brandy and Mr. Whiskers, Ed, Edd n Eddy, Courage, Mickey Mouse cartoons, Invader Zim, Animanics, Freakaziod, and I think Sonic the Hedgehog...
Freakazoid: The best example was when a line Freakazoid said had the dialogue out of sync with the mouth movements. Then it cuts to Freakazoid saying "Let's watch the lip sync, okay." Then it cuts to a giant pair of lips sinking into the sea. Cuts back to Freakazoid who says, "Thank you!"
The Mask: The regular episodes that usually has the formula of Stanley Ipkiss losing the Mask somehow and has to get it back, it gets random. But the episodes where Stanley wears the Mask for the whole episode without taking it off, no bets are off on how wacky the show can get to. Travel through time, become vice-president, join the Marines, go on a chase to get a feather for a fedora while running into everything from homicidal exotic dancers to crazy bavarians. The Mask was a show that was truly crazy.
What about "Yellow Submarine"? I guess it counts as surrealistic/trippy rather than wacky, but still, we are talking about a movie that includes such things as:
*A sentient, evil flying glove
*Giant men (or maybe they were stiltwalkers) in tophats, that turn people to stone by throwing apples at them.
*A monster that eats everything, including the background and, in the end, itself.
In fact, the Chief Blue Meanie himself is pretty much the definition of wacky.
Animaniacs. One of the things I still remember about that show is the skit where Wakko burps a Mozart piece or something. Burping in melody is definitely wacky.