A term that Larry Niven invented, “flash crowd,” has entered the lexicon in a useful way. It’s sometimes called “flash mob,” which has an ethological ring reminiscent of “mobbing behaviour” by birds. Modern concepts are discovered this way: I believe it was Theodore Sturgeon who anticipated the traffic jam.
It has also been organized into a useful group effort. It’s like a barn-building “bee” that calls on participants to volunteer at random instead of calling one well-known neighbours.
Here’s an example: “Flash mob cataloging party.”
Mob cataloguing is also done online by people publishing photographs of their bookshelves and letting viewers catalogue what they see.
This represents a new and powerful way of using Internet contributions deliberately to accomplish tasks that otherwise would not attract the resources to do them.