Last year I worked in Saudi Arabia for a week solving a problem for a government hospital. I was paid with a riyal check. There was no time to cut a dollar check on their corresponding bank in New York so I got a stack of forty hundreds. I carried that back on the plane.

That amount is well under the limit for bringing cash into the country and I later declared it on my income tax forms.

Not an idiot in this case, but I wasn't particularly comfortable carrying the cash here... perfectly safe in Saudi though.