Oh, Cisco

A specific type of Tag. The plot is resolved just before the last Act Break, but the characters come back after the commercial and deliver one last joke, usually tangentially related to the plot. Very often afterwards, everyone laughs.

The trope name comes from The Cisco Kid, where Cisco would deliver the punchline, and Pancho would always go, "Oh, Ceeesco!" Still used in many shows, comedy or not.

Compare to And Knowing Is Half the Battle and End-of-Episode Silliness. Also compare with The Stinger, where this is after the credits. Usually a variation of Every Episode Ending.

Nothing to do with networking equipment. Or a certain bald federation captain.

Live-Action TV

 * Was common on the original Star Trek series. ("...where they'll be no tribble at all.")
 * Likewise, M*A*S*H.
 * The more refined version of this is the joke without words that goes on during the credits of Frasier.
 * Many episodes of My Name Is Earl play out the credits over a scene of Earl and Randy in bed having a conversation unconnected with the events of the episode, usually triggered by a Non Sequitur by Randy.
 * Disney Channel shows have some form of this, most notably That's So Raven and The Suite Life of Zack and Cody.
 * The Colbert Report has one last joke before the credits, generally delivered from Colbert's armchair by the fire (in reference to FDR's fireside chats). This can be anything from a one-liner to an entire scene.
 * Also, The Daily Show has the Moment of Zen.
 * The Avengers used these kinds of tag scenes.
 * The Brady Bunch always used these.
 * The Big Bang Theory often brings back a throw-away joke and expands on it, to humorous effect. In one episode, the gang
 * "What Did We Learn on the Show Tonight, Craig?" from The Late Late Show.
 * When the final joke happens after the credits it is known as The Stinger. Mystery Science Theater 3000 is famous for this.
 * The Blakes Seven episode "Children of Auron" where the premise is the almost total extermination of the Aurons, a race of empathic humanoids who are opposed to the evil Federation and are thus nominally allied with the protagonists. (Almost all alliances in Blake's Seven are nominal. It's their Hat.) Approximately five thousand children and a few adults survive and the crew manage to find them a location where they will be safe and can rebuild the Auron race. At the episode's close Avon makes a joke about the society being a gigantic nursery, which in the context of recent genocide is in incredibly poor taste. Auron main character Cally is notably absent from the bridge at this point.
 * Funky Squad.
 * Parodied in Police Squad!, along with the freeze frame ending.
 * Spoofed to hell and back in Garth Marenghi's Darkplace whenever one of the group makes a cheesy pun about what's just happened and the others laugh over-enthusiastically for a ridiculously long time.
 * Parodied in That's My Bush!; "Oh, Laura! One of these days, I'm gonna punch you in the face!"

Web Comics

 * This strip from VG Cats. Warning: May offend those who are offended by bloody baby fetuses. (Say that five times fast!)

Western Animation

 * I think the Superfriends did this too. Not like it helped or anything.
 * Used in every episode of The Proud Family.
 * The end of most Thundercats episodes.
 * Used on at least one occasion in Harvey Birdman, Attorney at Law.
 * Actually used with such regularity, an Adult Swim commercial was an entire montage of episode-concluding group laughing.
 * The Transformers and G.I. Joe ended a fair number of episodes this way.
 * Used in Whateley: The big idea. Nobody laughs, but it's an evil pun, though it spoils the culprit:.
 * Used at the end of Adventure Time episode "Slow Love" with Finn and Jake towards Beemo.