title: Magento: Deduct Tax at Checkout for (most) countries
body: <p>I am working on a UK fashion store. The customer has a specific requirement - never add tax (VAT) at checkout; rather, have VAT built into the price, and <em>deduct</em> when applicable.</p>
  
  <p>The use case is that EU purchases will have no tax added at checkout - as the price includes it. And, rest of the world purchases will have the VAT <em>deducted</em> at the checkout.</p>
  
  <p>I can't see how to do this in Magento. I though to set up some negative values for tax rates, but that doesn't work. </p>
  
  <p>Any ideas?</p>