I recently stumbled upon iCompta [http://www.lyricapps.com/iCompta/], a neat finance app for Mac OS X. Sadly the importing of the postbank csv files was a complete f***up 'cause one will end up mapping the csv header manually for each column.
Fortunately iCompta also supports the QIF... ...and guess what happened.
Straight forward - simply pipe it into your output file:
ruby postbank_qif.rb path_to_csv_file.csv > postbank.qif
{2010 Bascht}. Licensed under the MIT License: http://www.opensource.org/licenses/mit-license.php