Whip Pan

The Whip Pan is the act of panning the camera very rapidly from one subject to another, frequently blurring the images in between the subjects.

Used frequently in the more frenetic class of cartoon, in which it is exclusively referred to as "zip pan." Bonus points if it's accompanied by a "whoosh" sound effect or even an actual whip crack.

Used occasionally in live-action media to disguise a cut. This can be used to maintain the illusion of The Oner, or occasionally to make two scenes shot in completely different places seem like they're both in one setting.

Not to be confused with a kitchen utensil used by dominatrices.

Examples of Whip Pan include:

Anime

It happens in Serial Experiments Lain, complete with Speed Lines, for a conversation across a school gate. Because, well...
Happend once in K-On!.

Film

The "disguising a cut" variant is used to great effect in Joss Whedon's movie Serenity, where two long shots were connected by a whip pan to make the scene look like The Oner.
The movie $la$her$ disguised all cuts with pans, often whip pans to keep the pace of the action. Cuts were done when no actors were in the camera, maintaining the illusion that the entire movie was a single shot done by a single cameraman present in the scene.
Used frequently and hilariously in Hot Fuzz, accompanied by a whooshing sound.
- Also used sometimes in Spaced.
Used quite a few times at the beginning of the movie Snake Eyes, in order to join up separate shots to make the first 12 minutes of the film look like one continuous take when it really wasn't.
In the films, Spider-Man's Spider Sense is portrayed via a long Whip Pan from Spidey to the dangerous object, with a sound effect to indicate it.
The movie Wanted makes liberal use of these. The target. Whipshot that lasts thirty seconds and takes a circuitous route back to the person with the gun.
Citizen Kane - Uses Whip Pans in the breakfast table montage showing the deterioration of Kane's first marriage.
It's used to great effect in the trailer for Magnolia.
Robert Rodriguez used whip pans at least once to disguise a cut. Selma Hayek was unable to film with the rest of the cast for some reason, so in one scene, they whip pan back and forth between Selma and a few mooks standing in opposite ends of a room. Of course, each side of the room is a completely different set shot at completely different times.
- I seem to recall plenty of "whooshing" in this scene.

Live Action TV

Used on That '70s Show when the characters have been smoking marijuana and talking to each other. (Supposedly around the bong.)
Used frequently on NYPD Blue.
Standard scene-change method in Malcolm in the Middle, with whoosh.
Used on Corner Gas when it shows what someone's thinking.
Signifies a flashback on How I Met Your Mother.
This effect was used countless times on The Twilight Zone when Rod Serling shows up to introduce the story.
30 Rock used them to cut to "flashbacks" during its Live Episode.
Glee uses this for cuts.

Video Games

Phoenix Wright: Ace Attorney will often Whip Pan between the defense and prosecution, most often at the beginning of trials. This also happens between an attorney and the witness in the middle; when panning from one attorney to the other, the witness is not shown (possibly due to graphical limitations on creating a blur effect).

Western Animation

Total Drama Island often does this when two people in the confessional are talking about each other.

Gwen: (In confessional) Cody's like a little brother. An annoying little brother.
(Whip Pan to Cody playing Air guitar in confessional)

- Also done several times during Haute Camp-ture.

Courtney: Who would I vote for? ... I can't believe I'm saying this but... Duncan. Don't tell anyone!
(Camera zooms out to reveal fellow campers standing around her)
Beth: Oh, we already know. You were aaaall over him.
(Whip Pan to Noah sitting by the pool.)
Noah: My Golden Lab drools less over a rib-eye steak.

The Simpsons uses this in the opening.