Of all <a rel="nofollow" onclick="javascript:_gaq.push(['_trackPageview', '/outgoing/article_exit_link']);" href="http://www.wetdryvacuumcleaners.net">wet dry vacuum cleaners</a> through history, none has become such a household name as the Shop Vac. But what of the history of the Shop Vac that it should become such an important fixture in the American shop and...