F3 (Fight Flash Fraud or Fight Fake Flash) tests the full capacity
of a flash card (flash drive, flash disk, pendrive).  It writes to
the card and then checks if it can read it.  It will assure that
you haven't been sold a card with a smaller capacity than stated.

WARNING: All data on the tested disk might be lost!

WWW: http://oss.digirati.com.br/f3