Secret Discovery

Time for this week's puzzler.

Here it is. Very short, and very elegant.

During World War 2, the Japanese discovered a secret weapon, which they had hoped to use to their military advantage.

But it turns out, they did not. They did try, but it was not to their advantage.

And this discovery is something that is used by virtually every country in the world today, on a daily basis.

What was this discovery? And how was paper involved?

Good luck.

Answer the Puzzler »

Remember last week's puzzler?

Sweden Stops

This one is really quick. Here we go.

In Sweden, on a weekday in the 1960s at 5pm, all traffic in the whole country stopped.

A few moments later, it started up again, and has never been the same since.

What happened at 5pm that day? And why did it happen on a weekday?

Try not to use Google for this one! Honest answers only.