Thankfully I have not. I was behind someone in line once when they handed the clerk a counterfeit bill. They detained her while they called the authorities and she said she received it as change from another merchant.

No, but once at work somebody tried to use a movie prop 100 dollar bill to pay for their meal. It almost got accepted to, until we noticed it said "united statues of america"

Most certainly... a good portion of our old £1 coins were counterfeit.

I've also received old and foreign currency in my change, too...

Yes... and old and foreign currency, too. Change does wonders for my coin collection...

If I have, I didn't know it.

Yeah, a $20 bill

Yes $10 bill

too funny

Dunno.

I don’t think I have, although receiving foreign currency (Canadian coins or pesos) is always a possibility.

Not yet.