While there have been some real crappy episodes (the one where the kids had a school TV news show was just awful), there have been far more good ones. One of my favorites is where Cartman's hand becomes the new Jennifer Lopez and he wakes up to find Ben Asslick naked in his bed. That had classic lines like, "Oooh, Ben Affleck spooge!" and "Taco-flavored kisses for my Ben!" And I always seem to find myself watching "Bigger, Longer, and Uncut" when it comes on Comedy Central's Secret Stash.
Terrance: Philip, you're a dirty pig-f**ker!
Philip: Now Terrance, why would you say that?!
Terrance: Well, because you f**k pigs!
Philip: (after a short pause) Oh yeah!
Both: Hahahahahahahaha!
Ah... mindless toilet humor is great!