I think most participants in the Internet circa 1996 and personal computers in the early 1980s would understand this idea.
The Internet was being widely written off as a toy that many couldn't ever imagine having practical applications.
Case in point, this widely-cited piece from 1998:
> The growth of the Internet will slow drastically, as the flaw in "Metcalfe's law"--which states that the number of potential connections in a network is proportional to the square of the number of participants--becomes apparent: most people have nothing to say to each other! By 2005 or so, it will become clear that the Internet's impact on the economy has been no greater than the fax machine's.
http://web.archive.org/web/19980610100009/www.redherring.com...
Here are some fun things about this concept of toys turning into big things:
1. toys start out looking like toys, too
2. it's extremely difficult to distinguish the toys that will remain toys forever from those that will become "the next big thing."
A useful approach to the problem posed by (2) is to look at things that appear to be toys but refuse to die despite every indication that they should have done so long ago.
Toys that remain toys often have a trendiness and inelasticity to them that gives them naturally short lives. If you see a toy lingering long beyond the time it should have given up the ghost, you may be looking at the next big thing.
The next problem is that it can take a very long time for a toy to turn into the next big thing.