POW! ZAP! BLAM! No, not that kind of BLAM...the one where you're reading a comic book and then go..."Huh?"
Marvel Zombies 3 contains a scene where a superhero named Captain Mexica (who comes from an alternate timeline where the Aztec empire never fell) becomes infected and eats people, as he was a specimen collected for Earth-616. He is eventually cut in half by Machine Man. Of course, no-one ever discusses him before or after his appearances.
Of course, you can briefly see Captain Mexica in a flashback to the BLAM a few pages after Morbius starts video taping himself, dunno if that effects its BLAMness or not...
Just as Operation: Zero Tolerance was starting in the X-Men books, Jean is briefly KOed... the beginning of the next issue shows her meeting with Iron Man (who, along with half of the Marvel Universe, was presumed dead but had actually been sucked into a new universe). Before either of them can secure any answers, Jean is pulled back to Marvel 616 proper and this scene is never mentioned again. Word of God says this scene (and a few other power freak-outs Jean experienced) was supposed to have more relevance, but they dropped the plot point completely after the other Heroes returned.
Even The Dark Phoenix Saga, the biggest, most talked-about event in X-Men history, isn't free of these...in this case, it's "The Dramatic Debut Of The Dazzler!", wherein Cyclops and Phoenix meet the titular Dazzler thanks to Executive Meddling trying to create a multimedia superhero in the form of an Idol Singer. Although she became a fairly popular character in her own right later, the story of her introduction makes little sense in the larger context of the story being told.
The Tintin series has a mild one in The Broken Ear. An absent-minded professor leaves his house wearing his wife's overcoat and holding a cane like an umbrella, comes across a parrot, then mistakes it for a person when it speaks. It is a parrot that Tintin is trying to recapture, but there is no interaction with any of the other characters in the story while this vignette is going on, and it adds nothing to advance the story (the parrot has already been shown speaking, so it's not even that). Hergé in his fondness for absent-minded professors probably just wanted to throw in a moment of comic relief.
Crankshaft had a week-long series (starting here) that featured a much older Ed Crankshaft living in a nursing home combined with flashbacks to various baseball-related points in his life. Readers speculated that it was another "leap forward" similar to the one that had recently been done in Funky Winkerbean; others wondered if it was the beginning of the strip's conclusion. The next week, everything is back to normal. But what else would you expect in a newspaper comic?
The infamous, week-long, 1989 Garfield run "Garfield Alone" was a particularly creepy example of this. Garfield wakes up to find himself in an alternate reality where Odie and Jon are nowhere to be seen and he's all alone in a boarded-up, run-down, old uninhabited house, tormented by loneliness.
It should be noted that the sequence ends with Garfield seemingly willing himself into believing everything is back to normal, and thus the comic continues as if nothing ever happened. A popular interpretation is that everything that happens after this storyline is the result of Garfield's willful denial of reality, and that we've since been watching the delusions of a cat in an empty house who is slowly starving to death. This individual BLAM moment may have the unintended effect of turning the last 20 years of the comic into pure terror.
In Calvin and Hobbes, Calvin had always had many bizarre one-off fantasies, but a true BLAM was a continuing story where Calvin slowly got bigger and bigger until he fell off the Earth. Bill Watterson explained in the 10th anniversary book: "My original idea was to do this for a month and see how long readers would put up with it. I wisely chickened out, since the idea wasn't all that interesting to begin with. It's just weird for weirdness's sake, and I don't think it holds up very well."
Soon after the September 11th, 2001 terrorist attacks, The Boondocks dropped its regular cast and storylines in favor of "The Adventures Of Flagee and Ribbon," a pair of talking red, white, and blue patriotism props that provided social commentary measurably less subtle than the strip's standard narrative for a number of weeks before the strip returned to normal.
Tentative, as it wasn't used in the final version, but Don Simpson's adaptation of King Kong was originally to include a scene of Kong encountering the Hindenburg during his climb up the Empire State Building, whereupon he punches it out of the sky after becoming "instinctively enraged" at the sight of the Nazi swastikas on it, which is ironic given that Hitler's favourite movie was reportedly King Kong.
One happens during Hollis Mason's account of how he became Night Owl in Watchmen. Suddenly we cut to a story about Moe Vernon, the owner of an auto-repair shop who enjoys classical music and collecting tasteless novelty items, usually with a pornographic theme. One day while wearing a pair of fake breasts and listening to Flight of the Valkyries in his office, he receives a letter from his wife informing him that she's been sleeping with Fred Motz, one of his employees who has taken the day off. Moe bursts out of his office wearing the fake breasts, the loud music playing dramatically in the background and bellows "Fred Motz has been having carnal knowledge of my wife." Thinking that it's a huge joke, his employees, including Hollis Mason's father burst out laughing. Moe later commits suicide. Having detailed the event, Hollis just goes back to the one he was telling before. It's a powerful story admittedly but has absolutely bugger all to do with anything. Mason admits that he got the idea from a friend, whose advice for hooking in the reader was simply "write the saddest thing you can think of," and the story serves as an opening to his biography, but its relevance to Watchmen is decidedly not there.
In the middle of an arc introducing Bo and Lanolin, a comic appeared showing Booker painting a smiley-face on a chair, then 2 few random strips about Sheldon, and a comic where Orson tells the reader how great snouts are. Usually, other arcs in the comic, like the one introducing Wade Duck and the one where the worm pretends to be a chicken, ended on Sundays-the arc in question ended on a Tuesday.
In Astérix and the Actress, both Asterix and Obelix have fallen in love with a Roman Honey Trap, Latraviata. This Love Triangle causes Obelix, who has Super Strength to Megaton Punch Asterix in the face. Getafix attempts to cure his strange behaviour by giving him Super Serum magic potion, which causes him to super-jump out to sea, flirt inanely with Latraviata, hit his head on a rock, regain his senses, drift around in a storm for a page, and then get rescued by a friendly bottlenose dolphin (in the English Channel...) in a partially literal Deus ex Machina (as Asterix states that it must be the protector god of the Gauls, Toutatis, saving him). He gets back, dries off, and it is never mentioned again, even though in order for the wackiness to ensue Obelix had to hit his own best friend in anger over a girl he had no chance with, and Asterix's relationship with Latraviata weirdly progresses. It seems very much like a filler segment to bring the comic up to 48 pages.