by Stephen Peters

Each file contains data of a different type (image files, programming languages, etc.), which would normally be represented using a different three-character extension. All documents are viewable through freely-available open-source programs (although many viewers/compilers won't be installed by default on every computer). Viewing the file or otherwise "playing" it will return one or more English words.

file extension, type phrase
001 AAC, audio file football franchise
002 AIF, audio file Song written by Sting
003 ASC, ascii-armored PGP Major educational institution
004 AVI, video Southwestern Lombardia
005 COB, COBOL program code count in casinospeak
006 DIA, Unix diagram editor file Singer with long hair who performed a ballad about
007 DVI, TeX output file near Sacramento
008 ELC, compiled Emacs code private yacht
009 EML, saved email Female figure skater
010 EPS, Encapsulated PostScript Name for the world's largest
011 ERL, Erlang program code Homer and Marge
012 FIG, xfig diagram Bahraini
013 GIF, image who won gold in 1968
014 ICO, Windows icon file Short name for what six
015 LUA, Lua script data Playboy
016 OTF, OpenType font data portraits and diptychs
017 RLE, image about an American civil engineer
018 SCM, Scheme program three majors might call their course
019 TAR, archive file logo maker
020 URL, Windows Internet shortcut carrier
021 UUE, uuencoded data Jean who was known for 15th century
022 XAR, Xara document Longest clue's word

The different phrases must then be paired up into clues, the answer to each of which will be a seven letter word containing the six letters in the file extensions, and an extra. By ordering the clues by the number of words, you get the following order:

The extra letters then spell APP USING QPW, or QUATTRO PRO.