it's usually a can of the black stuff. Sure, you could say that about virtually any draught beer, but any Guinness aficionado will tell you the art behind a good pint of Ireland's finest is in how ...

the beer exploded everywhere after the can was cracked open. In 1997, Guinness released the floating, spherical widget you can see in cans today - which they call the "Smoothifier" - to fix this ...