in reply to changing the file extension

Short answer: No.

Long answer: Renaming the file itself is trivial. Check out the rename() function. However, converting from text to Microsoft Word format is something entirely different. You'll want to look at the RTF modules on CPAN.

xoxo,
Andy

%_=split/;/,".;;n;u;e;ot;t;her;c; ".   #   Andy Lester
'Perl ;@; a;a;j;m;er;y;t;p;n;d;s;o;'.  #   http://petdance.com
"hack";print map delete$_{$_},split//,q<   andy@petdance.com   >