I am posting this here just as a friendly warning. My brother-in-law just returned from BA, Argentina. While there, they took a taxi and the taxista offered to exchange money for them. The taxista returned some small Argentinian bills that were real, but the majority (about $110 USD worth) was fake (color photocopies really!). Not being familiar with the local currency, BIL just took the money and *poof* the taxista was gone. They didn't realize it was fake until they tried to buy some shoes and the store owner refused the money. Looking at it closely, it is surely fake.
A sad lesson, but hoping that by posting here, people who might be bound for ARG will at least be aware of the scam. =(
As in my subject line, this is probably not the first post of this, nor the last, but worth bumping the subject to the top. =(