John Adams

John Adams exists in Futurama's twisted future as one more preserved head in a jar, a relic of the Head Museum where history's famous faces are kept alive for centuries as trivia and punchlines. He shows up briefly, dignified and slightly baffled by his diminished circumstances, a founding father reduced to a curiosity.

The joke is the whole point: a man who helped found a nation is now a jarred exhibit, wheeled out for a sight gag about immortality's indignities. John DiMaggio, a voice actor with an ear for wounded pomposity, gives the head just enough gravity to make the absurdity land without straining for the laugh.