Boomhauer

Boomhauer leans on Hank Hill's truck most afternoons, one of the guys who gather in the alley to drink beer and watch the world go by. He's easygoing, unexpectedly successful with women, handy with a guitar, and talks in a rapid, run-on mumble that somehow everyone but the audience seems to understand perfectly.

The joke is structural: an entire character built out of a vocal tic, voiced by Mike Judge in a fast, slurred drawl that never once slows down for clarity. What makes it work is the show's refusal to subtitle him or let anyone react to the strangeness — the world just accepts him, which makes the gag funnier every single time it recurs.