The Win32 part is not exactly true:

open LPR, ">LPT1:"
  or die "Couldn't open printer";
print LWP <>;
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Will print out a text file on the printer, much like the lpr command. Of course, there are no fancy postscript interpreters behind that... But printing any non-trivial file under Windows 2000 or higher can be done with the following, provided that there is the appropriate registry entry for the file type:

my $file = 'foo.xls';
system("print $file");
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