Two factor LUKS decryption

Security tells us to use VeryLongAnd$t0ngPasswordWithStr4ng3And$pecia!Characters to crypt our LUKS ( disks, but it is very booring and error prone: in this article I'll tell you how to setup your Debian ( system to use also a short password (like a PIN) AND an USB key to decrypt the LUKS disk, without loosing any security. (...)