Basic Travel Allowance (BTA).

BTA is a common ruse used by scammers.

From http://london.usembassy.gov/cons_new/ac ... scams.html

Beware of anyone who requests funds for a BTA, or Basic Travel Allowance, as a requirement to depart another country for the United States. There is no such thing as a BTA. In other cases, your Internet friend will claim to need a travel allowance, or travel money, to be able to travel to the United States. Again, there is no such requirement under U.S. law.

BTA did exist, but was the exact opposite of what scammers claim it to be. It was a maximum amount of money a person could take out of a country, not a minimum amount a person was allowed to have in order to be allowed into a country.