If I run the sentence "TheDamian writes perlish code on perlmonks", which doesn't contain any word that is extremely rare on this site, through "spell", it finds three unknown words.

This is a cutie too:

for f in /usr/local/share/perl/lib/5.8.3/pod/*.pod
do pod2text $f
done | spell | wc -l
   9154
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