interesting idea. Yes, Windows NTFS does support sparse files. to make one...see below.

One link http://msdn.microsoft.com/en-us/library/aa365564(VS.85).aspx
Google "windows sparse file" for others including "FSUTIL Sparse" command line manager on Win XP.

#!/usr/bin/perl -w
use strict;

open(FILE, ">", "sparse") || die "unable to open for write\n";

print FILE "some stuff";
seek(FILE,1000000,0);
print FILE "more stuff";
close FILE;
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