Spider-Man: Homecoming has two extra scenes. Airplane! (1980) has one. Guardians Of The Galaxy Vol. 2 (2017) has five.
Appearing during the end credits, these are called tags, stingers and credit cookies - but not all are worth biting into.
In Spider-Man: Homecoming, which opens in cinemas tomorrow, one of them is related to the movie plot and features a key character. The other is more of a throwaway gag and it could either tickle your funny bone or test your patience.
There has been a noticeable proliferation of these scenes in recent years. Superhero flicks such as Spider-Man are the main culprit, I mean, main reason, for the spike.
With a Marvel Cinematic Universe of inter-related superhero films, the extra scenes are often teasers for movies to come. In Iron Man (2008), Samuel L. Jackson made a surprise cameo as Nick Fury from the agency S.H.I.E.L.D. and he brought up The Avengers initiative.
After the credits for Captain America: Civil War (2016), we saw Peter Parker (Tom Holland) lying in bed as his aunt, May (Marisa Tomei), asked about his injuries, pointing the way to Spider-Man: Homecoming.
Other times, though, things get a little too complicated.
The extra scene in Avengers: Age Of Ultron (2015) showed supervillain Thanos (Josh Brolin) vowing to retrieve the all-powerful Infinity Stones himself. It looked towards the two-part Avengers: Infinity War, slated to hit cinemas in the next two years. Unless one was already a fan of the comic books, it was hard to figure out what was going on.
Maybe it is time for a moratorium on these bonus scenes. If they were that integral to the film, they would have made it to the part before the credits.
The extra scenes have spawned a cottage industry online.
There are websites, such as What's After The Credits? (aftercredits.com) and MediaStinger (mediastinger.com), that detail credit cookies and what they contain and even explanatory videos on YouTube.
MediaStinger also has a ratings chart to indicate whether the extras are worth staying on for - because, the truth is, few of them are actually that memorable.
How many can you recall? Can you say which was the best one without first heading to the sites mentioned earlier?
What works for me are the playful extras. They are not even necessarily scenes, but a bit of welcome comic relief.
Pixar is particularly good at this. A Bug's Life (1998), for example, featured bloopers by the cast of insects. But, of course, there is no such thing as a bloopers reel for an animated film and each "outtake" has to be scripted and computer-animated from scratch.
Another animation company, Illumination Entertainment, also did well with Despicable Me (2010), in which a trio of the mischievous minions hammed it up during the credits as they competed to see who could stretch out farthest into the audience - a cute gag that also showcased the 3D effects.
Best of all are the outtakes in action superstar Jackie Chan's movies. They are nothing less than an institution - where you witness the blood, sweat and tears, sometimes literally, that go into the insane stunts that he attempts for the sake of entertaining audiences.
In Armour Of God (1986), we see the accident that almost took his life when a tree branch he leapt onto broke and he plummeted 5m to the ground. He is carried off on a stretcher, amazingly enough still conscious, while holding up a piece of cloth to the right side of his head to staunch the bleeding.
Now, that definitely stings.
