Watch the border security shows. If they catch you with undeclared cash over $10k, it will be confiscated if you can't prove the source and they'll tell you to "suck it" and you leave with 10k less. Of course everything is fine if they don't catch you but that's the same with drugs and all other contraband.
This is an incorrect midset that the government appears to share. If I bring over $10,000 in cash across the US border I have to declare it and they may freak out. If I bring a credit card with a $100,000 limit across the border and spend $100,000 the next day I don't have to tell anyone. Or load that amount on stored value cards, for those of you sure the gubmnt is monitoring all credit card transactions. Either way the government has much more control over crossborder money movement if it is cash.
Not folklore - it is a fact. US Customs - How much currency can I bring into or take out of the U.S.? IMO ..... It best to cooperate with border guards.
What is this a tin-hat party? You can do international wires in amount greater then 10K w/out issue. If you are doing it for illegal purposes and somebody asks, you'r probably fucked. However this is not relevant to me and last I checked this was not a thread about how to fund terrorism or evade taxes (hello NSA). If you are carrying cash greater then 10K into the country and you don't declare it you'r either 1) doing something illegal, 2) "you forgot" 'cos you got piss drunk on the plane, or 3) you'r a half-wit, in either case, you probably deserve confiscation, and possibly castration.