Excellent, indeed!

And, FWIW, wgannon's code appears to work fine on W2K, at least for the OS key; the Ofc key can be adapted, trivially, by changing both instances of "11.0" to whatever version you find (via regedit, for instance) at n.n in your registry at

HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Office\\n.n
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but I'm not positive it works correctly as running the adapted code here spews what seems to me to be a highly unlikely key -- but that may be because the Ofc install here is a (thoroughly legal) US govt site license, to which only the systems folk have access.

Just in case my n.n notation is unclear, my changed lines are:

my @office = $Registry->{"HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Off
+ice\\9.0\\Registration"}->SubKeyNames;
print &getXPkey("HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Office\\9.0\
+\Registration\\$office[0]\\\\DigitalProductId");
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