Margie's arrest of Gaear Grimsrud. When Marge, weapon drawn, yells "Police!" at Grimsrud — and then points at the badge on her forehead — that's crowningly awesome.
Chirpy, good-natured Sheriff Marge Gunderson is a winning character, waddling through a kidnapping/multiple-homicide investigation with a quick mind that belies her seeming small-town hick exterior, but her final monologue to sullen, brutally psychotic killer Gaear Grimsrud (whom she has single-handedly arrested and brought to justice — not a bad feat itself considering he's over six foot of pure psycho and she's seven months pregnant) is probably her Crowning Moment:
Marge: [Sadly] So that was Mrs. Lundegaard on the floor in there. And I guess that was your accomplice in the wood chipper. And those three people in Brainerd. And for what? For a little bit of money. There's more to life than a little money, you know. Don't you know that? And here ya are, and it's a beautiful day. Well, I just don't understand it.
Our weedy, rodent-like, quibbles-over-a-few-bucks-with-parking-lot-attendants Anti-Villain Carl (Steve Buscemi), is on the edge of his tether, but bear in mind just half an hour ago we saw him turn white at the sight of blood. He goes to pick up the money in a parking lot and shoots the protagonist's father-in-law in the gut. He gets shot back, non-fatally, in the face/neck, does Buscemi's trademark "You fucking shot me!", shoots the guy about eight times, and shoots the parking lot attendant for good measure. Then he staggers back to his hideout covered in blood, sees his partner notice his appearance and remarks,
"You should see the other guy."
Awesome Music: The whole score, but particularly the music during the aforementioned arrest. And that bit at the very beginning when the car is cresting the hill in the opening credits.