It was in the early days of Win95.

Another one I had fun with was something I did before the prank app.

I don’t know if it will still work these days (I haven’t done it since ¹), but …

Create a folder on a shared resource.

Give it an enticing name, to encourage people to look inside it.

Create a hardlink to that folder, inside the folder itself.

Give it an enticing name … like … oh, I don’t know … something like, say …

DO NOT OPEN THIS FOLDER

When people open the hardlink, what they see is a view of the parent folder … which looks, for all the World, as though the hardlink hadn’t opened.

So, they try again.

And again,

And again.

And again.

And …

Eventually the stack overloads and their system freezes.

—
¹ I’m not sure if that’s because I’ve matured … or because companies are more tech savvy these days and I’d get caught 😉