If this assignment were part of an obfuscation contest, I would say this: 

$_=$,;$,=$/;$/=$_;$_=<DATA>;print/([-_a-z_-]+)\x2eco(?:m|m?\x2e[a-z][a
+-z])\s/gi;
__DATA__
http://www.tesco.com http://www.mmu.ac.uk http://www.amazon.com http:/
+/www.ikea.co.uk http://plus.maths.org

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In reply to Re: Web Address Validation by hdb
in thread Web Address Validation by scuttsuk

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