Adventure Time, on Cartoon Network
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I watched an episode or two of this when it first started. I liked it, but it was on opposite other, more important stuff, I guess, so I didn't get to see any more of it. But eventually I did watch some more, though I still never got to see it as regularly as I might like. And later still, I lost access to Cartoon Network, so I've completely missed at least a couple of seasons. I'd really like to catch up someday, especially since it seems to have developed a massive cult following. Anyway, it's a pretty fun show, kind of retro, a very simplistic and weird cartoon, very imaginative and childish, but also something that should appeal to grown-ups. (If I ever do get to catch up on the whole series, I might raise my rating somewhat.)
It's set in the Land of Ooo, which is comprised several different regions. There's a human boy named Finn, who wants to be a hero. He lives in a treehouse in the Grass Lands with his best friend, a talking dog named Jake who can stretch his limbs and grow to just about any size (or shrink, I guess). And they have adventures together. Mainly, as far as I can tell from what little I've seen, they work for Princess Bubblegum, who lives in the Candy Kingdom. Also from what little I've seen, the main villain is the Ice King, who lives in the Ice Kingdom and has a crown that gives him magic powers. There's another region called Lumpy Space, and... I dunno, plenty of other regions, I guess. But I'm sure there are plenty of other characters and all kinds of stuff about the show that I don't know yet. But I doubt any of it is really important. Like I said, it's basically a simple show about a boy and his dog having silly, surreal adventures. I dunno what else to say. Each ep is just 15 minutes long and there's not much in the way of plot. It all seems kinda random and fun, kind of like looking into the imagination of a young child who doesn't know anything about writing. And that's a good thing. Cuz it makes you feel like a young child, yourself. I guess.
Oh, and if you like (or love) this, you should definitely check out the webseries Bravest Warriors and Bee and PuppyCat.