Vertical align an inline-block element using parents pseudo element :before or :after. Doesn't matter the height of the parent or the height of the element.

valign-inline-block.css

#parent { font-size: 0px; }
  #parent:before { content: ''; display: inline-block; height: 100%; vertical-align: middle; }
  #element { display: inline-block; vertical-align: middle; font-size: 10px; }