All files in the game and editor data are plain text, except these extensions:

*.bik;*.bnk;*.bshd;*.bullet;*.cur;*.dat;*.data;*.dds;*.fnt;*.gr2;*.iggy;*.iggytex;*.lsb;*.lsf;*.lsfx;*.osi;*.patch;*.png;*.swf;*.tga;*.tmpl;*.ttf

However, most of the binary formats can be opened in existing programs, and others can be converted to readable formats.